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.
(1) In its target cells, nitric oxide (NO) leads to an increase in this second messenger:
(2) 5α-Reductase catalyzes the conversion of testosterone to __________.
(3) Which of the following hormone(s) is/are not stored in secretory vesicles before release from endocrine cells?
(4) In general, hormone secretion can be either constitutive or regulated.
(5) The exocytotic release of hormones stored in secretory vesicles is triggered by a rise in cytoplasmic __________ concentration.
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Posted: Thursday, January 28, 2016 Last updated: Thursday, January 28, 2016