Answer:
D
Explanation:
Hormones are bigger than the cell pores hence cannot pass through the cell membrane to influence biochemical processes. Therefore, hormones (such as glucagon and insulin) bind onto receptors on the cell membrane, then transmembrane proteins, such as the G-protein, change conformation activating the secondary messengers inside of the cell. Cyclic- AMP is a major secondary messenger significant in activating protein kinases.
Clear-cutting is the most common method of timber removal. Clear-cutting removes all the trees in a given area, often by using large machinery. From an economic standpoint, the benefit of this approach is that humans can harvest maximum timber with minimal energy and cost.
A buildup of pesticides could get into an animal. That animal will be killed by a hunter. The hunter eats the animal with the pesticide. The hunter then becomes sick. This is just an example but you can see what i'm getting at.
C. two populations become reproductively isolate; no inter mating occurs.
