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Glossary of Physiology Terms
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There are 6 glossary search results for:   weight




Definition:
Body weight that exceeds the normal or standard weight range. The standard range is generally determined based on height and frame size.

Related glossary terms/phrases:
Body Mass Index

See also:
Body Mass Index Calculator



Abbreviation:
BMI

Definition:
The body mass index is measured by dividing body weight (in kilograms) by body height (in meters) squared (kg / m2). It is highly correlated with body composition, and higher BMI values are correlated with higher body fat content. The BMI value is used to classify one's weight in several categories including underweight, normal, overweight, and obese. The range of BMI values considered to be normal is 18.5 to 24.9. Higher BMI values are associated with an increased risk for diseases such as diabetes mellitus type II, hypertension, and cardiovascular disease.

See also:
Body Mass Index Calculator

Other resources:
Body mass index (Wikipedia)



Definition:
Glutamate (Glu, E) is one of the standard twenty (20) amino acids used by cells to synthesize peptides, polypeptides, and proteins. It has a molecular weight of 147.13 g/mol. Its side chain has a pKa of 4.07 and, therefore, glutamate has a net negative charge at physiological pH.

In the nervous system, glutamate is an excitatory amino acid neurotransmitter. In fact, glutamate is the most abundant excitatory neurotransmitter in the nervous system. Glutamate is a classical neurotransmitter. Its action is exerted via the activation of glutamate receptors (GluR), some of which are ligand-gated ion channels (ionotropic receptors), and some are G protein coupled receptors (GPCRs, metabotropic receptors). At glutamatergic synapses, the action of glutamate is terminated by glutamate transporters (EAAT, excitatory amino acid transporter), which transport glutamate from the extracellular space in synaptic and extrasynaptic regions into neurons and glia.



Definition:
Glycine (Gly, G) is one of the standard twenty (20) amino acids. At a molecular weight of 75.07 g/mol, it is the smallest of the 20 amino acids used by cells to synthesize peptides, polypeptides, and proteins.

In the nervous system, glycine is also an inhibitory amino acid neurotransmitter. Glycinergic synapses are most commonly found in brain stem and spinal cord circuits. Glycine is a classical neurotransmitter. Its action is exerted via the activation of ionotropic glycine receptors (GlyR), which are ligand-gated chloride channels. At glycinergic synapses, the action of glycine is terminated by glycine transporters (GlyT), which transport glycine from the extracellular space in synaptic and extrasynaptic regions into neurons and glia.



Definition:
Hyperthyroidism refers to a pathophysiological condition in which the thyroid gland produces and releases abnormally high levels of the thyroid hormones (T3 and T4).

The symptoms of hyperthyroidism may include high metabolic rate, weight loss, nervousness, excess heat production, tachycardia, and tremor.

Two main forms of hyperthyroidism exist: (1) Primary hyperthyroidism, and (2) Secondary hyperthyroidism.

In primary hyperthyroidism, the thyroid gland produces high levels of the thyroid hormones, either as a result of a secretory tumor of the thyroid gland, or under the control of thyroid stimulating immunoglobulins (such as in Graves' disease).

Secondary hypothyroidism is caused by high levels of thyroid stimulating hormone (TSH) produced by the anterior pituitary gland. TSH then stimulates the thyroid gland to produce excessive amounts of the thyroid hormones.

Related glossary terms/phrases:
Hypothyroidism
Euthyroidism



Definition:
Hypothyroidism refers to a pathophysiological condition in which the thyroid gland does not produce sufficient amounts of the thyroid hormones (underactive thyroid), leading to abnormally low levels of the thyroid hormones (T3 and T4).

The symptoms of hypothyroidism may include reduced metabolic rate, chronic fatigue, weight gain, myxedema, and depression.

Three main forms of hypothyroidism exist: (1) Primary hypothyroidism, (2) Secondary hypothyroidism, and (3) Tertiary hypothyroidism.

In primary hypothyroidism, the thyroid gland itself is incapable of producing normal levels of the thyroid hormones.

Secondary hypothyroidism is caused by low levels of thyroid stimulating hormone (TSH). TSH, produced by the anterior pituitary gland, is required to stimulate the thyroid gland to produce the thyroid hormones.

Tertiary hypothyroidism is caused by low levels of thyrotropin releasing hormone (TRH). TRH, produced by the hypothalamus, is required to stimulate the anterior pituitary gland to produce TSH which, in turn, is required to stimulate the thyroid gland to produce the thyroid hormones.

Related glossary terms/phrases:
Primary hypothyroidism
Secondary hypothyroidism
Tertiary hypothyroidism

Hyperthyroidism
Euthyroidism









Posted: Sunday, March 31, 2013
Last updated: Friday, August 28, 2015