You are having lunch with an elderly friend when suddenly he begins to experience chest pain and tightness. He reaches into his pocket, gets out one of his nitroglycerin tablets and quickly takes it. After the episode passes, your friend asks you how the nitroglycerin helps his angina. You explain that nitroglycerin gets converted by cells to nitric oxide (NO) causing the smooth muscle cells of the blood vessel to relax and increase blood flow to the heart. He pushes you for a more detailed explanation, so you explain further that:
A. NO activates a protein kinase which catalyzes the synthesis of cGMP, which acts as an intracellular messenger in a pathway leading to smooth muscle relaxation.
B. NO activates guanylyl cyclase, which catalyzes the synthesis of cGMP, which acts as an intracellular messenger in a pathway leading to smooth muscle relaxation.
C. NO inhibits guanylyl cyclase, which allows the build up of cGMP, which acts as an intracellular messenger in a pathway leading to smooth muscle relaxation.
D. NO activates cGMP, which catalyzes the synthesis of guanylyl cyclase, which acts as an intracellular messenger in a pathway leading to smooth muscle relaxation.
Answer: B
You might also like to view...
Match the term on the left with its definition or description on the right.
A) energy from carbon, carbon from sunlight B) electron donor is water C) energy from sunlight, carbon from organic sources D) electron donor is carbon dioxide E) energy from sunlight, carbon from CO2 F) light-dependent generation of NADPH G) use electron donors such as sulfide and thiosulfate 1) photoreduction 2) photoheterotrophs 3) photoautotrophs 4) oxygenic phototrophs 5) anoxygenic phototrophs
If a cell contains 84 sister chromatids at metaphase of mitosis, how many chromosomes will be present in each
nucleus in late telophase?
a. 168 b. 84 c. 42 d. 21 e. cannot be determined from the information given
Describe two classes of proteins known to be involved in the regulation of the cell cycle
What will be an ideal response?
An invertebrate biologist is conducting research with crabs. Her interest is ecdysis. This implies that she studies
A. how ocelli evolved from mere photoreceptors to imaging lens. B. how the HOX gene controls the fusion of the head and thorax into the cephalothorax. C. tagmatization processes in crustaceans. D. the molting process. E. how ommatidia function individually in a compound eye.