Concept explainers
Interpretation:
It should be determined that how the given stimulants (Caffeine and theobromine) might interact with an enzyme in the cAMP pathway to enhance the effect of cAMP.
Concept introduction:
Stimulants: These are a group of drugs with many potential therapeutic uses, but also widely used and abused recreationally. Stimulants improve mood, enhance alertness and relieve depression.
Caffeine, Nicotine, Cocaine, Ecstasy … are some examples for stimulants.
cAMP is a cyclic
Enzymes are proteins that increase the
Secondary messengers are short lived intracellular signaling molecules. Elevated concentration of these type of messengers leads to rapid alteration in the activity of one or more cellular enzymes.
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- Someone goes for a jog first thing in the morning and encounters a squadron of javelinas, causing a release of epinephrine. Some of this circulating epinephrine binds to a G-alpha-s coupled receptor (GPCR) on the surface of muscle cells. Which of the following would occur in the muscle cell as a result of this activation? Nitric oxide synthesis would increase. cyclic AMP (cAMP) activity would increase. Phospholipase C (PLC) would hydrolyze (cut) the molecule PIP2. The levels of adenylate cyclase activity would decrease. The levels of adenylate cyclase activity would decrease. Which ligand is CORRECTLY matched with its characteristic? Group of answer choices Glucagon: stimulates the activation of the mitogen activated protein (MAP) kinase pathway Nitric oxide (NO): must bind to its target protien withn a few seconds because NO degrades rapidly Steroid hormone: produces a response in its target cells within seconds Acetylcholine: hydrophobic molecule that binds to…arrow_forwardThe secondary messenger cyclic AMP (cAMP) is involved in many different signaling pathways, including the G protein-coupled receptor (GPCR) pathway. Which of the following describes an advantage of using cAMP as a secondary messenger in cell signaling? It conserves energy because cAMP can be converted to ATP. It increases signaling specificity because protein kinase A, the direct effector of cAMP, has few substrates. It prolongs the signal because cAMP is chemically stable and persists for a long time after ligand dissociation. It amplifies the signal because one molecule of activated adenylyl cyclase can produce many molecules of cAMP.arrow_forwardname and describe the isoforms of the leptin receptor.arrow_forward
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