Answer:
B) cAMP
Explanation:
Phosphodiesterase is an enzyme that breaks a phosphodiester bond, for example in molecules such as cAMP and cGMP. So, phosphodiestarases are are regulators of signal transduction: regulate the duration of signaling pathway.
Caffeine is central-nervous-system stimulant and the mechanisms of its action usually are: mobilization of intracellular calcium or inhibition of specific phosphodiesterases.
Answer: C
Explanation: Subduction is a geological process that takes place at convergent boundaries of tectonic plates where one plate moves under another and is forced to sink due to high gravitational potential energy into the mantle. Regions where this process occurs are known as subduction zones.
Answer:
b
Explanation:
The R in RNA stands for Ribosomes which are proteins.
Answer:
C. A hillside that has been cleared by a volcanic eruption.
Explanation:
Pioneer species are hardy species which are the first to colonize barren environments or previously biodiverse steady-state ecosystems that have been disrupted, such as by fire or other natural disasters. Some lichens grow on rocks without soil, so may be among the first of life forms, and break down the rocks into soil for plants.
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