Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

The cardiac cycle refers to the sequence of events that takes place from one heart beat to the next. A full understanding of the cardiac cycle requires thorough examination of atrial systole, atrial diastole, ventricular systole, ventricular diastole, atrial and ventricular volume changes during the cycle, electrical events (depolarization and repolarization) of atria and ventricular myocytes, heart sounds associated with turbulent blood flow caused by the closure of semilunar valves, as well as hydrostatic blood pressure changes within the atria, ventricles, and the aorta. Test you basic understanding of the cardiac cycle by taking this simple quiz. Take quiz...

The cardiac cycle refers to the sequence of events that takes place from one heart beat to the next. A full understanding of the cardiac cycle requires thorough examination of atrial systole, atrial diastole, ventricular systole, ventricular diastole, atrial and ventricular volume changes during the cycle, electrical events (depolarization and repolarization) of atria and ventricular myocytes, heart sounds associated with turbulent blood flow caused by the closure of semilunar valves, as well as hydrostatic blood pressure changes within the atria, ventricles, and the aorta. Test you basic understanding of the cardiac cycle by taking this simple quiz. Take quiz...

The cardiac cycle refers to the sequence of events that takes place from one heart beat to the next. A full understanding of the cardiac cycle requires thorough examination of atrial systole, atrial diastole, ventricular systole, ventricular diastole, atrial and ventricular volume changes during the cycle, electrical events (depolarization and repolarization) of atria and ventricular myocytes, heart sounds associated with turbulent blood flow caused by the closure of semilunar valves, as well as hydrostatic blood pressure changes within the atria, ventricles, and the aorta. Test you basic understanding of the cardiac cycle by taking this simple quiz. Take quiz...

The cardiac cycle refers to the sequence of events that takes place from one heart beat to the next. A full understanding of the cardiac cycle requires thorough examination of atrial systole, atrial diastole, ventricular systole, ventricular diastole, atrial and ventricular volume changes during the cycle, electrical events (depolarization and repolarization) of atria and ventricular myocytes, heart sounds associated with turbulent blood flow caused by the closure of semilunar valves, as well as hydrostatic blood pressure changes within the atria, ventricles, and the aorta. Test you basic understanding of the cardiac cycle by taking this simple quiz. Take quiz...

The cardiac cycle refers to the sequence of events that takes place from one heart beat to the next. A full understanding of the cardiac cycle requires thorough examination of atrial systole, atrial diastole, ventricular systole, ventricular diastole, atrial and ventricular volume changes during the cycle, electrical events (depolarization and repolarization) of atria and ventricular myocytes, heart sounds associated with turbulent blood flow caused by the closure of semilunar valves, as well as hydrostatic blood pressure changes within the atria, ventricles, and the aorta. Test you basic understanding of the cardiac cycle by taking this simple quiz. Take quiz...

The cardiac cycle refers to the sequence of events that takes place from one heart beat to the next. A full understanding of the cardiac cycle requires thorough examination of atrial systole, atrial diastole, ventricular systole, ventricular diastole, atrial and ventricular volume changes during the cycle, electrical events (depolarization and repolarization) of atria and ventricular myocytes, heart sounds associated with turbulent blood flow caused by the closure of semilunar valves, as well as hydrostatic blood pressure changes within the atria, ventricles, and the aorta. Test you basic understanding of the cardiac cycle by taking this simple quiz. Take quiz...

The cardiovascular system is composed of the heart and blood vessels. The basic function of the heart is to pump blood through the blood vessels. The basic function of the blood vessels is to serve as conduits to carry blood away from the heart to the tissues, and to return blood from the tissues back to heart. Test your basic knowledge of cardiovascular physiology by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

The evolution of signaling molecules has made it possible for cells of multicellular organisms, such as humans, to communicate with one another in simple and complex ways. Signaling molecules may be used to transmit information between cells (extracellular or intercellular signaling), or they may be involved in signaling cascades inside cells (cytoplasmic or intracellular signaling). Test your basic knowledge of signaling molecules by taking this simple quiz. Take quiz...

The evolution of signaling molecules has made it possible for cells of multicellular organisms, such as humans, to communicate with one another in simple and complex ways. Signaling molecules may be used to transmit information between cells (extracellular or intercellular signaling), or they may be involved in signaling cascades inside cells (cytoplasmic or intracellular signaling). Test your basic knowledge of signaling molecules by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Abnormal function of the endocrine system may result from a number of different causes. These pathophysiological states of the endocrine system or endocrinopathies may be caused by the absence of hormone, underproduction of hormone, overproduction of hormone, abnormal hormone transport in blood, absence or abnormal function of hormone receptors, or absence or abnormal function of one or more of the cytoplasmic signaling cascades required for normal hormone action. Test your basic knowledge of endocrine pathophysiology by taking this simple quiz. Take quiz...

The evolution of signaling molecules has made it possible for cells of multicellular organisms, such as humans, to communicate with one another in simple and complex ways. Signaling molecules may be used to transmit information between cells (extracellular or intercellular signaling), or they may be involved in signaling cascades inside cells (cytoplasmic or intracellular signaling). Test your basic knowledge of signaling molecules by taking this simple quiz. Take quiz...

Abnormal function of the endocrine system may result from a number of different causes. These pathophysiological states of the endocrine system or endocrinopathies may be caused by the absence of hormone, underproduction of hormone, overproduction of hormone, abnormal hormone transport in blood, absence or abnormal function of hormone receptors, or absence or abnormal function of one or more of the cytoplasmic signaling cascades required for normal hormone action. Test your basic knowledge of endocrine pathophysiology by taking this simple quiz. Take quiz...

Abnormal function of the endocrine system may result from a number of different causes. These pathophysiological states of the endocrine system or endocrinopathies may be caused by the absence of hormone, underproduction of hormone, overproduction of hormone, abnormal hormone transport in blood, absence or abnormal function of hormone receptors, or absence or abnormal function of one or more of the cytoplasmic signaling cascades required for normal hormone action. Test your basic knowledge of endocrine pathophysiology by taking this simple quiz. Take quiz...

Abnormal function of the endocrine system may result from a number of different causes. These pathophysiological states of the endocrine system or endocrinopathies may be caused by the absence of hormone, underproduction of hormone, overproduction of hormone, abnormal hormone transport in blood, absence or abnormal function of hormone receptors, or absence or abnormal function of one or more of the cytoplasmic signaling cascades required for normal hormone action. Test your basic knowledge of endocrine pathophysiology by taking this simple quiz. Take quiz...

The evolution of signaling molecules has made it possible for cells of multicellular organisms, such as humans, to communicate with one another in simple and complex ways. Signaling molecules may be used to transmit information between cells (extracellular or intercellular signaling), or they may be involved in signaling cascades inside cells (cytoplasmic or intracellular signaling). Test your basic knowledge of signaling molecules by taking this simple quiz. Take quiz...

The evolution of signaling molecules has made it possible for cells of multicellular organisms, such as humans, to communicate with one another in simple and complex ways. Signaling molecules may be used to transmit information between cells (extracellular or intercellular signaling), or they may be involved in signaling cascades inside cells (cytoplasmic or intracellular signaling). Test your basic knowledge of signaling molecules by taking this simple quiz. Take quiz...

The evolution of signaling molecules has made it possible for cells of multicellular organisms, such as humans, to communicate with one another in simple and complex ways. Signaling molecules may be used to transmit information between cells (extracellular or intercellular signaling), or they may be involved in signaling cascades inside cells (cytoplasmic or intracellular signaling). Test your basic knowledge of signaling molecules by taking this simple quiz. Take quiz...

The evolution of signaling molecules has made it possible for cells of multicellular organisms, such as humans, to communicate with one another in simple and complex ways. Signaling molecules may be used to transmit information between cells (extracellular or intercellular signaling), or they may be involved in signaling cascades inside cells (cytoplasmic or intracellular signaling). Test your basic knowledge of signaling molecules by taking this simple quiz. Take quiz...

The evolution of signaling molecules has made it possible for cells of multicellular organisms, such as humans, to communicate with one another in simple and complex ways. Signaling molecules may be used to transmit information between cells (extracellular or intercellular signaling), or they may be involved in signaling cascades inside cells (cytoplasmic or intracellular signaling). Test your basic knowledge of signaling molecules by taking this simple quiz. Take quiz...

The evolution of signaling molecules has made it possible for cells of multicellular organisms, such as humans, to communicate with one another in simple and complex ways. Signaling molecules may be used to transmit information between cells (extracellular or intercellular signaling), or they may be involved in signaling cascades inside cells (cytoplasmic or intracellular signaling). Test your basic knowledge of signaling molecules by taking this simple quiz. Take quiz...

The kidneys are of outstanding importance. They perform a number of homeostatic functions including filtration of plasma and elimination of metabolic waste products, regulation of the composition and volume of the extracellular fluid, and regulation of blood pressure. The kidneys are also endocrine organs. Test your basic knowledge of renal physiology by taking this simple quiz. Take quiz...

The kidneys are of outstanding importance. They perform a number of homeostatic functions including filtration of plasma and elimination of metabolic waste products, regulation of the composition and volume of the extracellular fluid, and regulation of blood pressure. The kidneys are also endocrine organs. Test your basic knowledge of renal physiology by taking this simple quiz. Take quiz...

The kidneys are of outstanding importance. They perform a number of homeostatic functions including filtration of plasma and elimination of metabolic waste products, regulation of the composition and volume of the extracellular fluid, and regulation of blood pressure. The kidneys are also endocrine organs. Test your basic knowledge of renal physiology by taking this simple quiz. Take quiz...

The kidneys are of outstanding importance. They perform a number of homeostatic functions including filtration of plasma and elimination of metabolic waste products, regulation of the composition and volume of the extracellular fluid, and regulation of blood pressure. The kidneys are also endocrine organs. Test your basic knowledge of renal physiology by taking this simple quiz. Take quiz...

The kidneys are of outstanding importance. They perform a number of homeostatic functions including filtration of plasma and elimination of metabolic waste products, regulation of the composition and volume of the extracellular fluid, and regulation of blood pressure. The kidneys are also endocrine organs. Test your basic knowledge of renal physiology by taking this simple quiz. Take quiz...

The kidneys are of outstanding importance. They perform a number of homeostatic functions including filtration of plasma and elimination of metabolic waste products, regulation of the composition and volume of the extracellular fluid, and regulation of blood pressure. The kidneys are also endocrine organs. Test your basic knowledge of renal physiology by taking this simple quiz. Take quiz...

The kidneys are of outstanding importance. They perform a number of homeostatic functions including filtration of plasma and elimination of metabolic waste products, regulation of the composition and volume of the extracellular fluid, and regulation of blood pressure. The kidneys are also endocrine organs. Test your basic knowledge of renal physiology by taking this simple quiz. Take quiz...

The kidneys are of outstanding importance. They perform a number of homeostatic functions including filtration of plasma and elimination of metabolic waste products, regulation of the composition and volume of the extracellular fluid, and regulation of blood pressure. The kidneys are also endocrine organs. Test your basic knowledge of renal physiology by taking this simple quiz. Take quiz...

The kidneys are of outstanding importance. They perform a number of homeostatic functions including filtration of plasma and elimination of metabolic waste products, regulation of the composition and volume of the extracellular fluid, and regulation of blood pressure. The kidneys are also endocrine organs. Test your basic knowledge of renal physiology by taking this simple quiz. Take quiz...

Movement of fluid across the capillary wall is governed by hydrostatic pressure differences as well as osmotic pressure differences across the capillary wall. Test your basic knowledge of this process by taking this simple quiz. Take quiz...

Movement of fluid across the capillary wall is governed by hydrostatic pressure differences as well as osmotic pressure differences across the capillary wall. Test your basic knowledge of this process by taking this simple quiz. Take quiz...

Movement of fluid across the capillary wall is governed by hydrostatic pressure differences as well as osmotic pressure differences across the capillary wall. Test your basic knowledge of this process by taking this simple quiz. Take quiz...

The kidneys are of outstanding importance. They perform a number of homeostatic functions including filtration of plasma and elimination of metabolic waste products, regulation of the composition and volume of the extracellular fluid, and regulation of blood pressure. The kidneys are also endocrine organs. Test your basic knowledge of renal physiology by taking this simple quiz. Take quiz...

The kidneys are of outstanding importance. They perform a number of homeostatic functions including filtration of plasma and elimination of metabolic waste products, regulation of the composition and volume of the extracellular fluid, and regulation of blood pressure. The kidneys are also endocrine organs. Test your basic knowledge of renal physiology by taking this simple quiz. Take quiz...

The kidneys are of outstanding importance. They perform a number of homeostatic functions including filtration of plasma and elimination of metabolic waste products, regulation of the composition and volume of the extracellular fluid, and regulation of blood pressure. The kidneys are also endocrine organs. Test your basic knowledge of renal physiology by taking this simple quiz. Take quiz...

The kidneys are of outstanding importance. They perform a number of homeostatic functions including filtration of plasma and elimination of metabolic waste products, regulation of the composition and volume of the extracellular fluid, and regulation of blood pressure. The kidneys are also endocrine organs. Test your basic knowledge of renal physiology by taking this simple quiz. Take quiz...

The kidneys are of outstanding importance. They perform a number of homeostatic functions including filtration of plasma and elimination of metabolic waste products, regulation of the composition and volume of the extracellular fluid, and regulation of blood pressure. The kidneys are also endocrine organs. Test your basic knowledge of renal physiology by taking this simple quiz. Take quiz...

The kidneys are of outstanding importance. They perform a number of homeostatic functions including filtration of plasma and elimination of metabolic waste products, regulation of the composition and volume of the extracellular fluid, and regulation of blood pressure. The kidneys are also endocrine organs. Test your basic knowledge of renal physiology by taking this simple quiz. Take quiz...

The kidneys are of outstanding importance. They perform a number of homeostatic functions including filtration of plasma and elimination of metabolic waste products, regulation of the composition and volume of the extracellular fluid, and regulation of blood pressure. The kidneys are also endocrine organs. Test your basic knowledge of renal physiology by taking this simple quiz. Take quiz...

The kidneys are of outstanding importance. They perform a number of homeostatic functions including filtration of plasma and elimination of metabolic waste products, regulation of the composition and volume of the extracellular fluid, and regulation of blood pressure. The kidneys are also endocrine organs. Test your basic knowledge of renal physiology by taking this simple quiz. Take quiz...

The kidneys are of outstanding importance. They perform a number of homeostatic functions including filtration of plasma and elimination of metabolic waste products, regulation of the composition and volume of the extracellular fluid, and regulation of blood pressure. The kidneys are also endocrine organs. Test your basic knowledge of renal physiology by taking this simple quiz. Take quiz...

The kidneys are of outstanding importance. They perform a number of homeostatic functions including filtration of plasma and elimination of metabolic waste products, regulation of the composition and volume of the extracellular fluid, and regulation of blood pressure. The kidneys are also endocrine organs. Test your basic knowledge of renal physiology by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

A good understanding of the physiology of the nervous system requires a thorough knowledge of the molecules, cells, and tissues that make up the central and peripheral nervous systems. Test your basic knowledge of the organization of the nervous system by taking this simple quiz. Take quiz...

This quiz contains a set of questions randomly selected from different topics. Take quiz...

This quiz contains a set of questions randomly selected from different topics. Take quiz...

This quiz contains a set of questions randomly selected from different topics. Take quiz...

This quiz contains a set of questions randomly selected from different topics. Take quiz...

Thirst is a basic and intrinsic craving for drinking fluids. When the plamsa concentration of ions increases as a result of dehydration or blood loss, thirst is stimulated in order to replenish the water lost. Test your basic knowledge of thirst physiology by taking this simple quiz. Take quiz...

Thirst is a basic and intrinsic craving for drinking fluids. When the plamsa concentration of ions increases as a result of dehydration or blood loss, thirst is stimulated in order to replenish the water lost. Test your basic knowledge of thirst physiology by taking this simple quiz. Take quiz...

Thirst is a basic and intrinsic craving for drinking fluids. When the plamsa concentration of ions increases as a result of dehydration or blood loss, thirst is stimulated in order to replenish the water lost. Test your basic knowledge of thirst physiology by taking this simple quiz. Take quiz...

Thirst is a basic and intrinsic craving for drinking fluids. When the plamsa concentration of ions increases as a result of dehydration or blood loss, thirst is stimulated in order to replenish the water lost. Test your basic knowledge of thirst physiology by taking this simple quiz. Take quiz...

Test your basic knowledge of blood, its composition, and its functions by taking this simple quiz. Take quiz...

The auditory system is responsible for converting sound waves in the environment into electrical signals that the brain can receive and utilize as useful information about the sound characteristics of the external environment. Test your basic knowledge of auditory physiology by taking this simple quiz. Take quiz...

In order to have a solid understanding of physiological principles, it is essential that one understand the organization of body fluid compartments, as well as the composition of the fluids in these compartments. Test your understanding of body fluid compartments by taking this simple quiz. Take quiz...

The auditory system is responsible for converting sound waves in the environment into electrical signals that the brain can receive and utilize as useful information about the sound characteristics of the external environment. Test your basic knowledge of auditory physiology by taking this simple quiz. Take quiz...

The main function of neurons is to receive information, process this information, formulate an appropriate response, and then transmit this response to other cells. Information is transmitted to another cell across a synapse. The neuron sending the information is referred to as the pre-synaptic neuron. The cell receiving the information at the other end of the synapse is called the post-synaptic cell. The post-synaptic cell can be another neuron, a muscle cell, an endocrine cell, or other cell type. Much of information processing in the brain takes place at the level of the synapse. Test your basic knowledge of synaptic neurotransmission by taking this simple quiz. Take quiz...

The auditory system is responsible for converting sound waves in the environment into electrical signals that the brain can receive and utilize as useful information about the sound characteristics of the external environment. Test your basic knowledge of auditory physiology by taking this simple quiz. Take quiz...

The auditory system is responsible for converting sound waves in the environment into electrical signals that the brain can receive and utilize as useful information about the sound characteristics of the external environment. Test your basic knowledge of auditory physiology by taking this simple quiz. Take quiz...

The auditory system is responsible for converting sound waves in the environment into electrical signals that the brain can receive and utilize as useful information about the sound characteristics of the external environment. Test your basic knowledge of auditory physiology by taking this simple quiz. Take quiz...

In learning and understanding the principles of physiology (or any other discipline), it is often helpful to have a knowledge of the key events as well as scientists responsible for major discoveries that led to the current dogma accepted by most people in the field. Test your basic knowledge of the history of physiology by taking this simple quiz. Take quiz...

The auditory system is responsible for converting sound waves in the environment into electrical signals that the brain can receive and utilize as useful information about the sound characteristics of the external environment. Test your basic knowledge of auditory physiology by taking this simple quiz. Take quiz...

The auditory system is responsible for converting sound waves in the environment into electrical signals that the brain can receive and utilize as useful information about the sound characteristics of the external environment. Test your basic knowledge of auditory physiology by taking this simple quiz. Take quiz...

The auditory system is responsible for converting sound waves in the environment into electrical signals that the brain can receive and utilize as useful information about the sound characteristics of the external environment. Test your basic knowledge of auditory physiology by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

The auditory system is responsible for converting sound waves in the environment into electrical signals that the brain can receive and utilize as useful information about the sound characteristics of the external environment. Test your basic knowledge of auditory physiology by taking this simple quiz. Take quiz...

The auditory system is responsible for converting sound waves in the environment into electrical signals that the brain can receive and utilize as useful information about the sound characteristics of the external environment. Test your basic knowledge of auditory physiology by taking this simple quiz. Take quiz...

The auditory system is responsible for converting sound waves in the environment into electrical signals that the brain can receive and utilize as useful information about the sound characteristics of the external environment. Test your basic knowledge of auditory physiology by taking this simple quiz. Take quiz...

The auditory system is responsible for converting sound waves in the environment into electrical signals that the brain can receive and utilize as useful information about the sound characteristics of the external environment. Test your basic knowledge of auditory physiology by taking this simple quiz. Take quiz...

The auditory system is responsible for converting sound waves in the environment into electrical signals that the brain can receive and utilize as useful information about the sound characteristics of the external environment. Test your basic knowledge of auditory physiology by taking this simple quiz. Take quiz...

The auditory system is responsible for converting sound waves in the environment into electrical signals that the brain can receive and utilize as useful information about the sound characteristics of the external environment. Test your basic knowledge of auditory physiology by taking this simple quiz. Take quiz...

Hemoglobin dramatically increase the oxygen carrying capacity of blood, serving to transport large volumes of oxygen from respiratory organs to metabolically active tissues, which allows for the maintenance of the high metabolic rate enjoyed by vertebrate animals. Test your basic knowledge of hemoglobin by taking this simple quiz. Take quiz...

The auditory system is responsible for converting sound waves in the environment into electrical signals that the brain can receive and utilize as useful information about the sound characteristics of the external environment. Test your basic knowledge of auditory physiology by taking this simple quiz. Take quiz...

The auditory system is responsible for converting sound waves in the environment into electrical signals that the brain can receive and utilize as useful information about the sound characteristics of the external environment. Test your basic knowledge of auditory physiology by taking this simple quiz. Take quiz...

The auditory system is responsible for converting sound waves in the environment into electrical signals that the brain can receive and utilize as useful information about the sound characteristics of the external environment. Test your basic knowledge of auditory physiology by taking this simple quiz. Take quiz...

The auditory system is responsible for converting sound waves in the environment into electrical signals that the brain can receive and utilize as useful information about the sound characteristics of the external environment. Test your basic knowledge of auditory physiology by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

In learning and understanding the principles of physiology (or any other discipline), it is often helpful to have a knowledge of the key events as well as scientists responsible for major discoveries that led to the current dogma accepted by most people in the field. Test your basic knowledge of the history of physiology by taking this simple quiz. Take quiz...

In spite of the importance of sleep to our mental, emotional, and physical well-being, our knowledge of the physiology of sleep is rather limited. We know from personal experience that lack of sleep leads to reduced mental alertness, diminished mental and physical performance, mood changes, and many other symptoms, all of which appear to be readily "cured" by getting "enough" sleep. Yet, how much sleep one needs is highly variable among individuals, and the reason for this variability is not at all clear. Human and animal studies are only beginning to elucidate the physiological factors and processes that are influenced by sleep deprivation. Test your basic knowledge of the physiology of sleep by taking this simple quiz. Take quiz...

Skeletal muscle cells are characterized by their striated appearance when visualized under the light and electron microscopes. Collectively, skeletal muscle cells make up approximately 50% of the body’s wet (i.e., soft tissue) weight. Skeletal muscle cells perform highly important functions including generating force, motion, and even heat. Test your basic knowledge of skeletal muscle physiology by taking this simple quiz. Take quiz...

In learning and understanding the principles of physiology (or any other discipline), it is often helpful to have a knowledge of the key events as well as scientists responsible for major discoveries that led to the current dogma accepted by most people in the field. Test your basic knowledge of the history of physiology by taking this simple quiz. Take quiz...

In learning and understanding the principles of physiology (or any other discipline), it is often helpful to have a knowledge of the key events as well as scientists responsible for major discoveries that led to the current dogma accepted by most people in the field. Test your basic knowledge of the history of physiology by taking this simple quiz. Take quiz...

In learning and understanding the principles of physiology (or any other discipline), it is often helpful to have a knowledge of the key events as well as scientists responsible for major discoveries that led to the current dogma accepted by most people in the field. Test your basic knowledge of the history of physiology by taking this simple quiz. Take quiz...

In order to have a complete understanding of physiological processes, it is often necessary to know gross anatomy as well as microscopic anatomy (i.e., histology). Often, it is important to know the number of a given structure under consideration. For example, a student of physiology should know the number of kidneys, nephrons, adrenal glands, cranial nerves, lungs, alveoli, etc. in the human body. Test your basic knowledge by taking this simple quiz. Take quiz...

In order to have a complete understanding of physiological processes, it is often necessary to know gross anatomy as well as microscopic anatomy (i.e., histology). Often, it is important to know the number of a given structure under consideration. For example, a student of physiology should know the number of kidneys, nephrons, adrenal glands, cranial nerves, lungs, alveoli, etc. in the human body. Test your basic knowledge by taking this simple quiz. Take quiz...

Test your knowledge of the basic principles of muscle physiology by taking this simple quiz. Take quiz...

Test your knowledge of the basic principles of muscle physiology by taking this simple quiz. Take quiz...

Test your knowledge of the basic principles of muscle physiology by taking this simple quiz. Take quiz...

The autonomic nervous system coordinates many bodily functions that are not generally under conscious control (i.e., involuntary functions). For example, the autonomic nervous system regulates the function of cardiac muscle, smooth muscle, and various glandular structures (e.g., sweat glands, salivary glands, and some endocrine glands). Test your basic knowledge of the autonomic nervous system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Excitable cells of the nervous system (i.e., neurons) generate nervous impulses. Nervous impulses are the electrical signals by which neurons talk to one another and also to other cells of the body. The nervous impulse is referred to as the action potential. An action potential is a brief (only a few milliseconds) reversal of the membrane potential (V_m). At rest, the V_m of a neuron is around −70 mV (closer to the equilibrium potential for potassium, V_K), but during an action potential, V_m transiently approaches +50 mV (closer to the equilibrium potential for sodium, V_Na). The membrane potential then rapidly returns to the resting potential and even briefly goes beyond the resting potential to approach V_K before finally returning to the resting value of about −70 mV. The entire process takes about 3-5 ms. This potential reversal of more than 100 mV is responsible for electrical signaling in the nervous system, and is the basis of information transmission in the nervous system. Take quiz...

Excitable cells of the nervous system (i.e., neurons) generate nervous impulses. Nervous impulses are the electrical signals by which neurons talk to one another and also to other cells of the body. The nervous impulse is referred to as the action potential. An action potential is a brief (only a few milliseconds) reversal of the membrane potential (V_m). At rest, the V_m of a neuron is around −70 mV (closer to the equilibrium potential for potassium, V_K), but during an action potential, V_m transiently approaches +50 mV (closer to the equilibrium potential for sodium, V_Na). The membrane potential then rapidly returns to the resting potential and even briefly goes beyond the resting potential to approach V_K before finally returning to the resting value of about −70 mV. The entire process takes about 3-5 ms. This potential reversal of more than 100 mV is responsible for electrical signaling in the nervous system, and is the basis of information transmission in the nervous system. Take quiz...

Excitable cells of the nervous system (i.e., neurons) generate nervous impulses. Nervous impulses are the electrical signals by which neurons talk to one another and also to other cells of the body. The nervous impulse is referred to as the action potential. An action potential is a brief (only a few milliseconds) reversal of the membrane potential (V_m). At rest, the V_m of a neuron is around −70 mV (closer to the equilibrium potential for potassium, V_K), but during an action potential, V_m transiently approaches +50 mV (closer to the equilibrium potential for sodium, V_Na). The membrane potential then rapidly returns to the resting potential and even briefly goes beyond the resting potential to approach V_K before finally returning to the resting value of about −70 mV. The entire process takes about 3-5 ms. This potential reversal of more than 100 mV is responsible for electrical signaling in the nervous system, and is the basis of information transmission in the nervous system. Take quiz...

Excitable cells of the nervous system (i.e., neurons) generate nervous impulses. Nervous impulses are the electrical signals by which neurons talk to one another and also to other cells of the body. The nervous impulse is referred to as the action potential. An action potential is a brief (only a few milliseconds) reversal of the membrane potential (V_m). At rest, the V_m of a neuron is around −70 mV (closer to the equilibrium potential for potassium, V_K), but during an action potential, V_m transiently approaches +50 mV (closer to the equilibrium potential for sodium, V_Na). The membrane potential then rapidly returns to the resting potential and even briefly goes beyond the resting potential to approach V_K before finally returning to the resting value of about −70 mV. The entire process takes about 3-5 ms. This potential reversal of more than 100 mV is responsible for electrical signaling in the nervous system, and is the basis of information transmission in the nervous system. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Puberty is a period of rapid physical growth and change, brought about by hormonal changes, that culminates in sexual maturity. Test your basic knowledge of human puberty by taking this simple quiz. Take quiz...

Puberty is a period of rapid physical growth and change, brought about by hormonal changes, that culminates in sexual maturity. Test your basic knowledge of human puberty by taking this simple quiz. Take quiz...

Puberty is a period of rapid physical growth and change, brought about by hormonal changes, that culminates in sexual maturity. Test your basic knowledge of human puberty by taking this simple quiz. Take quiz...

Puberty is a period of rapid physical growth and change, brought about by hormonal changes, that culminates in sexual maturity. Test your basic knowledge of human puberty by taking this simple quiz. Take quiz...

Puberty is a period of rapid physical growth and change, brought about by hormonal changes, that culminates in sexual maturity. Test your basic knowledge of human puberty by taking this simple quiz. Take quiz...

Caffeine, the most commonly consumed drug on the planet, is known to influence several physiological processes. Test your basic knowledge of the effect of caffeine on physiological systems by taking this simple quiz. Take quiz...

Caffeine, the most commonly consumed drug on the planet, is known to influence several physiological processes. Test your basic knowledge of the effect of caffeine on physiological systems by taking this simple quiz. Take quiz...

Caffeine, the most commonly consumed drug on the planet, is known to influence several physiological processes. Test your basic knowledge of the effect of caffeine on physiological systems by taking this simple quiz. Take quiz...

Caffeine, the most commonly consumed drug on the planet, is known to influence several physiological processes. Test your basic knowledge of the effect of caffeine on physiological systems by taking this simple quiz. Take quiz...

In order to learn physiology, it is essential that one understand many fundamental principles. Some of these principles are intrinsic to the discipline of physiology, while others are borrowed from disciplines such as molecular biology, cell biology, chemistry, physics, mathematics, computer science, psychology, engineering, and others. Test your knowledge of the fundamental principles of physiology by taking this simple quiz. Take quiz...

In order to learn physiology, it is essential that one understand many fundamental principles. Some of these principles are intrinsic to the discipline of physiology, while others are borrowed from disciplines such as molecular biology, cell biology, chemistry, physics, mathematics, computer science, psychology, engineering, and others. Test your knowledge of the fundamental principles of physiology by taking this simple quiz. Take quiz...

In order to learn physiology, it is essential that one understand many fundamental principles. Some of these principles are intrinsic to the discipline of physiology, while others are borrowed from disciplines such as molecular biology, cell biology, chemistry, physics, mathematics, computer science, psychology, engineering, and others. Test your knowledge of the fundamental principles of physiology by taking this simple quiz. Take quiz...

In order to learn physiology, it is essential that one understand many fundamental principles. Some of these principles are intrinsic to the discipline of physiology, while others are borrowed from disciplines such as molecular biology, cell biology, chemistry, physics, mathematics, computer science, psychology, engineering, and others. Test your knowledge of the fundamental principles of physiology by taking this simple quiz. Take quiz...

In order to learn physiology, it is essential that one understand many fundamental principles. Some of these principles are intrinsic to the discipline of physiology, while others are borrowed from disciplines such as molecular biology, cell biology, chemistry, physics, mathematics, computer science, psychology, engineering, and others. Test your knowledge of the fundamental principles of physiology by taking this simple quiz. Take quiz...

The function of the gastrointestinal tract (GI tract) is to process food. During this process, food is moved from the mouth to the anus. Feeding and drinking are voluntary activities, but are strongly influenced by signals from higher brain centers involved in the sensations of satiety and thirst. Once ingested, water and nutrients are extracted from food without any conscious control. Throughout the entire process, the ingested material is moved along the GI tract. Finally, the undigested and non-absorbed materials are released as feces from the anus (under voluntary control when socially appropriate!). Take quiz...

The function of the gastrointestinal tract (GI tract) is to process food. During this process, food is moved from the mouth to the anus. Feeding and drinking are voluntary activities, but are strongly influenced by signals from higher brain centers involved in the sensations of satiety and thirst. Once ingested, water and nutrients are extracted from food without any conscious control. Throughout the entire process, the ingested material is moved along the GI tract. Finally, the undigested and non-absorbed materials are released as feces from the anus (under voluntary control when socially appropriate!). Take quiz...

The function of the gastrointestinal tract (GI tract) is to process food. During this process, food is moved from the mouth to the anus. Feeding and drinking are voluntary activities, but are strongly influenced by signals from higher brain centers involved in the sensations of satiety and thirst. Once ingested, water and nutrients are extracted from food without any conscious control. Throughout the entire process, the ingested material is moved along the GI tract. Finally, the undigested and non-absorbed materials are released as feces from the anus (under voluntary control when socially appropriate!). Take quiz...

The function of the gastrointestinal tract (GI tract) is to process food. During this process, food is moved from the mouth to the anus. Feeding and drinking are voluntary activities, but are strongly influenced by signals from higher brain centers involved in the sensations of satiety and thirst. Once ingested, water and nutrients are extracted from food without any conscious control. Throughout the entire process, the ingested material is moved along the GI tract. Finally, the undigested and non-absorbed materials are released as feces from the anus (under voluntary control when socially appropriate!). Take quiz...

The function of the gastrointestinal tract (GI tract) is to process food. During this process, food is moved from the mouth to the anus. Feeding and drinking are voluntary activities, but are strongly influenced by signals from higher brain centers involved in the sensations of satiety and thirst. Once ingested, water and nutrients are extracted from food without any conscious control. Throughout the entire process, the ingested material is moved along the GI tract. Finally, the undigested and non-absorbed materials are released as feces from the anus (under voluntary control when socially appropriate!). Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Hemoglobin dramatically increase the oxygen carrying capacity of blood, serving to transport large volumes of oxygen from respiratory organs to metabolically active tissues, which allows for the maintenance of the high metabolic rate enjoyed by vertebrate animals. Test your basic knowledge of hemoglobin by taking this simple quiz. Take quiz...

Hemoglobin dramatically increase the oxygen carrying capacity of blood, serving to transport large volumes of oxygen from respiratory organs to metabolically active tissues, which allows for the maintenance of the high metabolic rate enjoyed by vertebrate animals. Test your basic knowledge of hemoglobin by taking this simple quiz. Take quiz...

Hemoglobin dramatically increase the oxygen carrying capacity of blood, serving to transport large volumes of oxygen from respiratory organs to metabolically active tissues, which allows for the maintenance of the high metabolic rate enjoyed by vertebrate animals. Test your basic knowledge of hemoglobin by taking this simple quiz. Take quiz...

The cardiovascular system is composed of the heart and blood vessels. The basic function of the heart is to pump blood through the blood vessels. The basic function of the blood vessels is to serve as conduits to carry blood away from the heart to the tissues, and to return blood from the tissues back to heart. Test your basic knowledge of cardiovascular physiology by taking this simple quiz. Take quiz...

The cardiovascular system is composed of the heart and blood vessels. The basic function of the heart is to pump blood through the blood vessels. The basic function of the blood vessels is to serve as conduits to carry blood away from the heart to the tissues, and to return blood from the tissues back to heart. Test your basic knowledge of cardiovascular physiology by taking this simple quiz. Take quiz...

The cardiovascular system is composed of the heart and blood vessels. The basic function of the heart is to pump blood through the blood vessels. The basic function of the blood vessels is to serve as conduits to carry blood away from the heart to the tissues, and to return blood from the tissues back to heart. Test your basic knowledge of cardiovascular physiology by taking this simple quiz. Take quiz...

The cardiovascular system is composed of the heart and blood vessels. The basic function of the heart is to pump blood through the blood vessels. The basic function of the blood vessels is to serve as conduits to carry blood away from the heart to the tissues, and to return blood from the tissues back to heart. Test your basic knowledge of cardiovascular physiology by taking this simple quiz. Take quiz...

The cardiovascular system is composed of the heart and blood vessels. The basic function of the heart is to pump blood through the blood vessels. The basic function of the blood vessels is to serve as conduits to carry blood away from the heart to the tissues, and to return blood from the tissues back to heart. Test your basic knowledge of cardiovascular physiology by taking this simple quiz. Take quiz...

The cardiovascular system is composed of the heart and blood vessels. The basic function of the heart is to pump blood through the blood vessels. The basic function of the blood vessels is to serve as conduits to carry blood away from the heart to the tissues, and to return blood from the tissues back to heart. Test your basic knowledge of cardiovascular physiology by taking this simple quiz. Take quiz...

Classical neurotransmitters refer to a small group of small molecule neurotransmitters. These neurotransmitters are used by the nervous system in a variety of circuits to transmit information from pre-synaptic neurons to post-synaptic cells. Test your basic knowledge of classical neurotransmitters by taking this simple quiz. Take quiz...

Classical neurotransmitters refer to a small group of small molecule neurotransmitters. These neurotransmitters are used by the nervous system in a variety of circuits to transmit information from pre-synaptic neurons to post-synaptic cells. Test your basic knowledge of classical neurotransmitters by taking this simple quiz. Take quiz...

Classical neurotransmitters refer to a small group of small molecule neurotransmitters. These neurotransmitters are used by the nervous system in a variety of circuits to transmit information from pre-synaptic neurons to post-synaptic cells. Test your basic knowledge of classical neurotransmitters by taking this simple quiz. Take quiz...

Transport of ions and molecules across biological membranes may occur by passive or active mechanisms and, indeed, membrane transport mechanisms form the basis for many important physiological processes. Test your basic knowledge of membrane transport by taking this simple quiz. Take quiz...

Transport of ions and molecules across biological membranes may occur by passive or active mechanisms and, indeed, membrane transport mechanisms form the basis for many important physiological processes. Test your basic knowledge of membrane transport by taking this simple quiz. Take quiz...

Transport of ions and molecules across biological membranes may occur by passive or active mechanisms and, indeed, membrane transport mechanisms form the basis for many important physiological processes. Test your basic knowledge of membrane transport by taking this simple quiz. Take quiz...

Transport of ions and molecules across biological membranes may occur by passive or active mechanisms and, indeed, membrane transport mechanisms form the basis for many important physiological processes. Test your basic knowledge of membrane transport by taking this simple quiz. Take quiz...

The pancreas is a compound gland. It is both an endocrine gland, and an exocrine gland. The exocrine pancreas plays a crucial role in food digestion by secreting digesting enzymes and bicarbonate into the duodenum portion of the small intestine. The endocrine part of the pancreas is responsible for secreting at least four important hormones, two of which, insulin and glucagon, play an important role in plasma glucose homeostasis. Test your basic knowledge of the endocrine pancreas by taking this simple quiz. Take quiz...

The pancreas is a compound gland. It is both an endocrine gland, and an exocrine gland. The exocrine pancreas plays a crucial role in food digestion by secreting digesting enzymes and bicarbonate into the duodenum portion of the small intestine. The endocrine part of the pancreas is responsible for secreting at least four important hormones, two of which, insulin and glucagon, play an important role in plasma glucose homeostasis. Test your basic knowledge of the endocrine pancreas by taking this simple quiz. Take quiz...

The pancreas is a compound gland. It is both an endocrine gland, and an exocrine gland. The exocrine pancreas plays a crucial role in food digestion by secreting digesting enzymes and bicarbonate into the duodenum portion of the small intestine. The endocrine part of the pancreas is responsible for secreting at least four hormones, two of which, insulin and glucagon, play an important role in plasma glucose homeostasis. Test your basic knowledge of the endocrine pancreas by taking this simple quiz. Take quiz...

There are approximately ten times as many glial cells in the nervous system as there are neurons. Collectively, the different types of glial cells perform very important functions in the nervous system. Test your basic knowledge of glial cells by taking this simple quiz. Take quiz...

There are approximately ten times as many glial cells in the nervous system as there are neurons. Collectively, the different types of glial cells perform very important functions in the nervous system. Test your basic knowledge of glial cells by taking this simple quiz. Take quiz...

There are approximately ten times as many glial cells in the nervous system as there are neurons. Collectively, the different types of glial cells perform very important functions in the nervous system. Test your basic knowledge of glial cells by taking this simple quiz. Take quiz...

Endocrinology is defined as the study of how chemical messenger molecules, referred to as hormones, influence physiological processes. By definition, a hormone is a signaling molecule that is released into the bloodstream, where the hormone can then travel to distant target cells and tissues within the body. Along with the nervous system, the hormones of the endocrine system provide an important means by which information travels within the body. Test your basic knowledge of the endocrine system by taking this simple quiz. Take quiz...

Classical neurotransmitters refer to a small group of small molecule neurotransmitters. These neurotransmitters are used by the nervous system in a variety of circuits to transmit information from pre-synaptic neurons to post-synaptic cells. Test your basic knowledge of classical neurotransmitters by taking this simple quiz. Take quiz...

Classical neurotransmitters refer to a small group of small molecule neurotransmitters. These neurotransmitters are used by the nervous system in a variety of circuits to transmit information from pre-synaptic neurons to post-synaptic cells. Test your basic knowledge of classical neurotransmitters by taking this simple quiz. Take quiz...

Classical neurotransmitters refer to a small group of small molecule neurotransmitters. These neurotransmitters are used by the nervous system in a variety of circuits to transmit information from pre-synaptic neurons to post-synaptic cells. Test your basic knowledge of classical neurotransmitters by taking this simple quiz. Take quiz...

Classical neurotransmitters refer to a small group of small molecule neurotransmitters. These neurotransmitters are used by the nervous system in a variety of circuits to transmit information from pre-synaptic neurons to post-synaptic cells. Test your basic knowledge of classical neurotransmitters by taking this simple quiz. Take quiz...

Classical neurotransmitters refer to a small group of small molecule neurotransmitters. These neurotransmitters are used by the nervous system in a variety of circuits to transmit information from pre-synaptic neurons to post-synaptic cells. Test your basic knowledge of classical neurotransmitters by taking this simple quiz. Take quiz...

Cardiac output is defined as the volume of blood pumped every minute by the left or right ventricle of the heart. Test your basic knowledge of cardiac output of the human heart by taking this simple quiz. Take quiz...

Smooth muscle is critically important to the function of the digestive system, reproductive system, respiratory system, vascular system (but not capillaries because their walls are composed of only a single layer of endothelial cells), urinary bladder, as well as many other organs. Test your basic knowledge of smooth muscle physiology by taking this simple quiz. Take quiz...

The autonomic nervous system coordinates many bodily functions that are not generally under conscious control (i.e., involuntary functions). For example, the autonomic nervous system regulates the function of cardiac muscle, smooth muscle, and various glandular structures (e.g., sweat glands, salivary glands, and some endocrine glands). Test your basic knowledge of the autonomic nervous system by taking this simple quiz. Take quiz...

The autonomic nervous system coordinates many bodily functions that are not generally under conscious control (i.e., involuntary functions). For example, the autonomic nervous system regulates the function of cardiac muscle, smooth muscle, and various glandular structures (e.g., sweat glands, salivary glands, and some endocrine glands). Test your basic knowledge of the autonomic nervous system by taking this simple quiz. Take quiz...

There are approximately ten times as many glial cells in the nervous system as there are neurons. Collectively, the different types of glial cells perform very important functions in the nervous system. Test your basic knowledge of glial cells by taking this simple quiz. Take quiz...

The thyroid gland is an endocrine gland whose hormone products perform many important functions. Test your basic knowledge of the thyroid gland, its hormone products, and the effect of these hormones on target tissues by taking this simple quiz. Take quiz...

The thyroid gland is an endocrine gland whose hormone products perform many important functions. Test your basic knowledge of the thyroid gland, its hormone products, and the effect of these hormones on target tissues by taking this simple quiz. Take quiz...

The thyroid gland is an endocrine gland whose hormone products perform many important functions. Test your basic knowledge of the thyroid gland, its hormone products, and the effect of these hormones on target tissues by taking this simple quiz. Take quiz...

The thyroid gland is an endocrine gland whose hormone products perform many important functions. Test your basic knowledge of the thyroid gland, its hormone products, and the effect of these hormones on target tissues by taking this simple quiz. Take quiz...

The thyroid gland is an endocrine gland whose hormone products perform many important functions. Test your basic knowledge of the thyroid gland, its hormone products, and the effect of these hormones on target tissues by taking this simple quiz. Take quiz...

The thyroid gland is an endocrine gland whose hormone products perform many important functions. Test your basic knowledge of the thyroid gland, its hormone products, and the effect of these hormones on target tissues by taking this simple quiz. Take quiz...

The thyroid gland is an endocrine gland whose hormone products perform many important functions. Test your basic knowledge of the thyroid gland, its hormone products, and the effect of these hormones on target tissues by taking this simple quiz. Take quiz...

The thyroid gland is an endocrine gland whose hormone products perform many important functions. Test your basic knowledge of the thyroid gland, its hormone products, and the effect of these hormones on target tissues by taking this simple quiz. Take quiz...

The thyroid gland is an endocrine gland whose hormone products perform many important functions. Test your basic knowledge of the thyroid gland, its hormone products, and the effect of these hormones on target tissues by taking this simple quiz. Take quiz...

The thyroid gland is an endocrine gland whose hormone products perform many important functions. Test your basic knowledge of the thyroid gland, its hormone products, and the effect of these hormones on target tissues by taking this simple quiz. Take quiz...

The thyroid gland is an endocrine gland whose hormone products perform many important functions. Test your basic knowledge of the thyroid gland, its hormone products, and the effect of these hormones on target tissues by taking this simple quiz. Take quiz...

The thyroid gland is an endocrine gland whose hormone products perform many important functions. Test your basic knowledge of the thyroid gland, its hormone products, and the effect of these hormones on target tissues by taking this simple quiz. Take quiz...

The thyroid gland is an endocrine gland whose hormone products perform many important functions. Test your basic knowledge of the thyroid gland, its hormone products, and the effect of these hormones on target tissues by taking this simple quiz. Take quiz...

The thyroid gland is an endocrine gland whose hormone products perform many important functions. Test your basic knowledge of the thyroid gland, its hormone products, and the effect of these hormones on target tissues by taking this simple quiz. Take quiz...

Test your basic knowledge of respiratory physiology by taking this simple quiz. Take quiz...

Test your basic knowledge of respiratory physiology by taking this simple quiz. Take quiz...

Test your basic knowledge of respiratory physiology by taking this simple quiz. Take quiz...

Test your basic knowledge of respiratory physiology by taking this simple quiz. Take quiz...

Test your basic knowledge of respiratory physiology by taking this simple quiz. Take quiz...

Test your basic knowledge of respiratory physiology by taking this simple quiz. Take quiz...

Test your basic knowledge of respiratory physiology by taking this simple quiz. Take quiz...

Test your basic knowledge of respiratory physiology by taking this simple quiz. Take quiz...

Test your basic knowledge of respiratory physiology by taking this simple quiz. Take quiz...

Test your basic knowledge of respiratory physiology by taking this simple quiz. Take quiz...

Test your basic knowledge of respiratory physiology by taking this simple quiz. Take quiz...

Test your basic knowledge of respiratory physiology by taking this simple quiz. Take quiz...

While physiology is the study of how living systems work, a good understanding of physical and chemical principles is essential to a solid understanding of physiological processes. A good starting point for learning about fundamental physical and chemical principles is to learn the commonly used fundamental physical constants, as well as other physical parameters, that are relevant to the study of physiology and other life sciences. Test your basic knowledge of fundamental physical constants by taking this simple quiz. For a quick refresher, see here. Take quiz...

Neuronal refractory periods occur after the onset of a neuronal action potential and represent a state of decreased neuronal excitability. Two types of refractory periods exist: absolute refractory period and relative refractory period. Test your basic knowledge of neuronal refractory periods by taking this simple quiz. Take quiz...

The Na⁺/K⁺ ATPase (or simply Na⁺ pump) is a ubiquitous membrane transport protein found in all body cell types. Test your basic knowledge of the Na⁺/K⁺ ATPase by taking this simple quiz. Take quiz...

The Na⁺/K⁺ ATPase (or simply Na⁺ pump) is a ubiquitous membrane transport protein found in all body cell types. Test your basic knowledge of the Na⁺/K⁺ ATPase by taking this simple quiz. Take quiz...

The Na⁺/K⁺ ATPase (or simply Na⁺ pump) is a ubiquitous membrane transport protein found in all body cell types. Test your basic knowledge of the Na⁺/K⁺ ATPase by taking this simple quiz. Take quiz...

The Na⁺/K⁺ ATPase (or simply Na⁺ pump) is a ubiquitous membrane transport protein found in all body cell types. Test your basic knowledge of the Na⁺/K⁺ ATPase by taking this simple quiz. Take quiz...

Fenestra is the Latin word for window. The plural form is fenestrae. Fenestrated capillaries are capillaries that have pores in their plasma membranes that allow the passage of fluid, ions, and small molecules. Test your basic knowledge of capillary fenestrae by taking this simple quiz. Take quiz...

In order to have a solid understanding of physiological principles, it is essential that one understand the organization of body fluid compartments, as well as the composition of the fluids in these compartments. Test your understanding of body fluid compartments by taking this simple quiz. Take quiz...

In order to have a solid understanding of physiological principles, it is essential that one understand the organization of body fluid compartments, as well as the composition of the fluids in these compartments. Test your understanding of body fluid compartments by taking this simple quiz. Take quiz...

In order to have a solid understanding of physiological principles, it is essential that one understand the organization of body fluid compartments, as well as the composition of the fluids in these compartments. Test your understanding of body fluid compartments by taking this simple quiz. Take quiz...

Maintenance of the normal pressure of blood within the vessels of the circulatory system is an essential feature of the cardiovascular system. Test your basic knowledge of hydrostatic blood pressure by taking this simple quiz. Take quiz...

Maintenance of the normal pressure of blood within the vessels of the circulatory system is an essential feature of the cardiovascular system. Test your basic knowledge of hydrostatic blood pressure by taking this simple quiz. Take quiz...

Maintenance of the normal pressure of blood within the vessels of the circulatory system is an essential feature of the cardiovascular system. Test your basic knowledge of hydrostatic blood pressure by taking this simple quiz. Take quiz...

The Na⁺/glucose cotransporter (SGLT) uses the energy stored in the transmembrane electrochemical gradient of Na⁺ to drive the uphill transport of glucose into cells against a glucose concentration gradient. While SGLTs are found in many tissues, they are prominently present in the apical membrane (i.e., brush border membrane) of epithelial cells in the small intestine and kidney proximal tubules. In the small intestine, Na⁺/glucose cotransport is essential for the absorption of glucose contained in ingested food across the wall of the small intestine. In the kidney proximal tubules, Na⁺/glucose cotransport is essential for the reabsoroption of glucose from the urine ultrafiltrate. Test your basic knowledge of Na⁺/glucose cotransporters by taking this simple quiz. Take quiz...

The Na⁺/glucose cotransporter (SGLT) uses the energy stored in the transmembrane electrochemical gradient of Na⁺ to drive the uphill transport of glucose into cells against a glucose concentration gradient. While SGLTs are found in many tissues, they are prominently present in the apical membrane (i.e., brush border membrane) of epithelial cells in the small intestine and kidney proximal tubules. In the small intestine, Na⁺/glucose cotransport is essential for the absorption of glucose contained in ingested food across the wall of the small intestine. In the kidney proximal tubules, Na⁺/glucose cotransport is essential for the reabsoroption of glucose from the urine ultrafiltrate. Test your basic knowledge of Na⁺/glucose cotransporters by taking this simple quiz. Take quiz...

Michaelis-Menten kinetics is used to describe the rate of a reaction catalyzed by an enzyme as a function of the substrate concentration. This type of analysis is also commonly used to describe the rate of transporter-mediated translocation of ions and molecules across biological membranes. Test your basic knowledge of Michaelis-Menten kinetics by taking this simple quiz. Take quiz...

Michaelis-Menten kinetics is used to describe the rate of a reaction catalyzed by an enzyme as a function of the substrate concentration. This type of analysis is also commonly used to describe the rate of transporter-mediated translocation of ions and molecules across biological membranes. Test your basic knowledge of Michaelis-Menten kinetics by taking this simple quiz. Take quiz...

Michaelis-Menten kinetics is used to describe the rate of a reaction catalyzed by an enzyme as a function of the substrate concentration. This type of analysis is also commonly used to describe the rate of transporter-mediated translocation of ions and molecules across biological membranes. Test your basic knowledge of Michaelis-Menten kinetics by taking this simple quiz. Take quiz...

Michaelis-Menten kinetics is used to describe the rate of a reaction catalyzed by an enzyme as a function of the substrate concentration. This type of analysis is also commonly used to describe the rate of transporter-mediated translocation of ions and molecules across biological membranes. Test your basic knowledge of Michaelis-Menten kinetics by taking this simple quiz. Take quiz...

The human heart is an amazing machine. During resting conditions, on average, the heart contracts (i.e., beats) 70 times per minute. Thus, the heart beats 4,200 times in one hour, 100,800 times in one day, 36,792,000 times in one year, and over a lifetime of 75 years, it beats 2,759,400,000 (2.7 billion times)! The heart's volume output (i.e., cardiac output) is also phenomenal. During resting conditions, on average, each ventricle pumps 4.9 liters (1.3 gallons) of blood every minute. Thus, each ventricle pumps 294 liters (77.7 gallons) of blood per hour, 7,056 liters (1,864 gallons) per day, 2,575,440 liters (680,359 gallons) per year, and over a lifetime of 75 years, 193,158,000 liters (51,026,945 gallons) of blood! As there are two ventricles, and the output of the left and right ventricles must be equal under healthy conditions, the total volume output of the heart is twice the numbers given. Test your basic knowledge of the human heart by taking this simple quiz. Take quiz...

The human heart is an amazing machine. During resting conditions, on average, the heart contracts (i.e., beats) 70 times per minute. Thus, the heart beats 4,200 times in one hour, 100,800 times in one day, 36,792,000 times in one year, and over a lifetime of 75 years, it beats 2,759,400,000 (2.7 billion times)! The heart's volume output (i.e., cardiac output) is also phenomenal. During resting conditions, on average, each ventricle pumps 4.9 liters (1.3 gallons) of blood every minute. Thus, each ventricle pumps 294 liters (77.7 gallons) of blood per hour, 7,056 liters (1,864 gallons) per day, 2,575,440 liters (680,359 gallons) per year, and over a lifetime of 75 years, 193,158,000 liters (51,026,945 gallons) of blood! As there are two ventricles, and the output of the left and right ventricles must be equal under healthy conditions, the total volume output of the heart is twice the numbers given. Test your basic knowledge of the human heart by taking this simple quiz. Take quiz...

Skeletal muscle cells are characterized by their striated appearance when visualized under the light and electron microscopes. Collectively, skeletal muscle cells make up approximately 50% of the body’s wet (i.e., soft tissue) weight. Skeletal muscle cells perform highly important functions including generating force, motion, and even heat. Test your basic knowledge of skeletal muscle physiology by taking this simple quiz. Take quiz...

Skeletal muscle cells are characterized by their striated appearance when visualized under the light and electron microscopes. Collectively, skeletal muscle cells make up approximately 50% of the body’s wet (i.e., soft tissue) weight. Skeletal muscle cells perform highly important functions including generating force, motion, and even heat. Test your basic knowledge of skeletal muscle physiology by taking this simple quiz. Take quiz...

Skeletal muscle cells are characterized by their striated appearance when visualized under the light and electron microscopes. Collectively, skeletal muscle cells make up approximately 50% of the body’s wet (i.e., soft tissue) weight. Skeletal muscle cells perform highly important functions including generating force, motion, and even heat. Test your basic knowledge of skeletal muscle physiology by taking this simple quiz. Take quiz...

Skeletal muscle cells are characterized by their striated appearance when visualized under the light and electron microscopes. Collectively, skeletal muscle cells make up approximately 50% of the body’s wet (i.e., soft tissue) weight. Skeletal muscle cells perform highly important functions including generating force, motion, and even heat. Test your basic knowledge of skeletal muscle physiology by taking this simple quiz. Take quiz...

Skeletal muscle cells are characterized by their striated appearance when visualized under the light and electron microscopes. Collectively, skeletal muscle cells make up approximately 50% of the body’s wet (i.e., soft tissue) weight. Skeletal muscle cells perform highly important functions including generating force, motion, and even heat. Test your basic knowledge of skeletal muscle physiology by taking this simple quiz. Take quiz...

The sarcomere is the functional unit of muscle cells. Test your basic knowledge of sarcomere structure and function by taking this simple quiz. Take quiz...

The sarcomere is the functional unit of muscle cells. Test your basic knowledge of sarcomere structure and function by taking this simple quiz. Take quiz...

The main function of neurons is to receive information, process this information, formulate an appropriate response, and then transmit this response to other cells. Information is transmitted to another cell across a synapse. The neuron sending the information is referred to as the pre-synaptic neuron. The cell receiving the information at the other end of the synapse is called the post-synaptic cell. The post-synaptic cell can be another neuron, a muscle cell, an endocrine cell, or other cell type. Much of information processing in the brain takes place at the level of the synapse. Test your basic knowledge of synaptic neurotransmission by taking this simple quiz. Take quiz...

The main function of neurons is to receive information, process this information, formulate an appropriate response, and then transmit this response to other cells. Information is transmitted to another cell across a synapse. The neuron sending the information is referred to as the pre-synaptic neuron. The cell receiving the information at the other end of the synapse is called the post-synaptic cell. The post-synaptic cell can be another neuron, a muscle cell, an endocrine cell, or other cell type. Much of information processing in the brain takes place at the level of the synapse. Test your basic knowledge of synaptic neurotransmission by taking this simple quiz. Take quiz...

The main function of neurons is to receive information, process this information, formulate an appropriate response, and then transmit this response to other cells. Information is transmitted to another cell across a synapse. The neuron sending the information is referred to as the pre-synaptic neuron. The cell receiving the information at the other end of the synapse is called the post-synaptic cell. The post-synaptic cell can be another neuron, a muscle cell, an endocrine cell, or other cell type. Much of information processing in the brain takes place at the level of the synapse. Test your basic knowledge of synaptic neurotransmission by taking this simple quiz. Take quiz...

The main function of neurons is to receive information, process this information, formulate an appropriate response, and then transmit this response to other cells. Information is transmitted to another cell across a synapse. The neuron sending the information is referred to as the pre-synaptic neuron. The cell receiving the information at the other end of the synapse is called the post-synaptic cell. The post-synaptic cell can be another neuron, a muscle cell, an endocrine cell, or other cell type. Much of information processing in the brain takes place at the level of the synapse. Test your basic knowledge of synaptic neurotransmission by taking this simple quiz. Take quiz...

In order to have a complete understanding of physiological processes, it is often necessary to know gross anatomy as well as microscopic anatomy (i.e., histology). Often, it is important to know the number of a given structure under consideration. For example, a student of physiology should know the number of kidneys, nephrons, adrenal glands, cranial nerves, lungs, alveoli, etc. in the human body. Test your basic knowledge by taking this simple quiz. Take quiz...

Cells of multicellular organisms such as animals and plants, as well as those of unicellular organisms such as yeast exhibit a potential difference across the cell plasma membrane. That is to say that there is an electrical potential difference between the inside of the cell and the surrounding bathing medium of the cell. This potential difference is referred to as the membrane potential (V_m). The numerical value of the membrane potential is generally negative, meaning that the inside of the cell is negative with respect to the outside solution, which is taken as the reference or zero value.

Test your knowledge of the membrane potential by taking this series of quizzes. For more information about the membrane potential, see the Resting Membrane Potential lecture notes. Take quiz...

Cells of multicellular organisms such as animals and plants, as well as those of unicellular organisms such as yeast exhibit a potential difference across the cell plasma membrane. That is to say that there is an electrical potential difference between the inside of the cell and the surrounding bathing medium of the cell. This potential difference is referred to as the membrane potential (V_m). The numerical value of the membrane potential is generally negative, meaning that the inside of the cell is negative with respect to the outside solution, which is taken as the reference or zero value.

Test your knowledge of the membrane potential by taking this series of quizzes. For more information about the membrane potential, see the Resting Membrane Potential lecture notes. Take quiz...

Cells of multicellular organisms such as animals and plants, as well as those of unicellular organisms such as yeast exhibit a potential difference across the cell plasma membrane. That is to say that there is an electrical potential difference between the inside of the cell and the surrounding bathing medium of the cell. This potential difference is referred to as the membrane potential (V_m). The numerical value of the membrane potential is generally negative, meaning that the inside of the cell is negative with respect to the outside solution, which is taken as the reference or zero value.

Test your knowledge of the membrane potential by taking this series of quizzes. For more information about the membrane potential, see the Resting Membrane Potential lecture notes. Take quiz...

Cells of multicellular organisms such as animals and plants, as well as those of unicellular organisms such as yeast exhibit a potential difference across the cell plasma membrane. That is to say that there is an electrical potential difference between the inside of the cell and the surrounding bathing medium of the cell. This potential difference is referred to as the membrane potential (V_m). The numerical value of the membrane potential is generally negative, meaning that the inside of the cell is negative with respect to the outside solution, which is taken as the reference or zero value.

Test your knowledge of the membrane potential by taking this series of quizzes. For more information about the membrane potential, see the Resting Membrane Potential lecture notes. Take quiz...

Did you know that the kidneys of an average adult human being filter about 180 L of plasma every day! That is every day, the entire volume of plasma is filtered about 50 times by the kidneys! This massive amount of filtration is indeed necessary to allow the kidneys to eliminate waste products present in the plasma. Most of these waste materials are the byproducts of normal metabolism. They are removed from the plasma through filtration (and secretion for some) in the kidneys and ultimately are eliminated from the body through urine. However, a significant amount (in fact most) of the filtered water must be reabsorbed in order to prevent life-threatening dehydration. Test your basic knowledge of kidney filtration and reabsorption by taking this simple quiz. Take quiz...

Excitable cells of the nervous system (i.e., neurons) generate nervous impulses. Nervous impulses are the electrical signals by which neurons talk to one another and also to other cells of the body. The nervous impulse is referred to as the action potential. An action potential is a brief (only a few milliseconds) reversal of the membrane potential (V_m). At rest, the V_m of a neuron is around −70 mV (closer to the equilibrium potential for potassium, V_K), but during an action potential, V_m transiently approaches +50 mV (closer to the equilibrium potential for sodium, V_Na). The membrane potential then rapidly returns to the resting potential and even briefly goes beyond the resting potential to approach V_K before finally returning to the resting value of about −70 mV. The entire process takes about 3-5 ms. This potential reversal of more than 100 mV is responsible for electrical signaling in the nervous system, and is the basis of information transmission in the nervous system.

Test your basic knowledge of the neuronal action potential by taking this simple quiz below. For more information about the neuronal action potential, see the Neuronal Action Potential lecture notes. Take quiz...

The Nobel Prize bestows upon a scientist the highest scientific honor possible. While most scientists pursue their intellectual passion without ever expecting to achieve fame, becoming a Nobel Prize recipient is the closest thing to "rock star" status for a scientist. Yet, it is often noted that many scientists have a limited knowledge of the history of the prize even in their own discipline. Test your knowledge of the past recipients of the Nobel Prize in Physiology or Medicine by taking this simple quiz. Take quiz...