I believe the first answer is C) evaporation. second answer B) transpiration, and the last answer is A) raindrops.
Answer:
Answer is D - cAMP.
Explanation:
cAMP is a small molecule that functions as an intracellular signaling molecule - a second messenger. The first messenger would be the thing that activated the GPCR (e.g. a hormone). The GPCR is a signal transducer (converts extracellular signal to intracellular signal). Once activated, the GPCR activates adenylate cyclase which can be called a signal effector - it is an enzyme that produces cAMP.
Plants and animals provide food for humans. Plants cycle the air for humans too.
Answer
Light intensity increases also, but it gets to a point that the temperature increases and denature the enzymes involved so a plateau results.
