What forms the channels in the phospholipid bilayer?
A) Hydrophilic Heads
B) Proteins
C) Carbohydrates
D) Lipids
The question had no answer labels, to I put them on myself.

answer: after carbon dioxide enters the leaf through stomata it moves into the mesophyll cells where photosynthesis occurs and glucose is constructed. respiration occurs when glucose (sugar produced during photosynthesis) combines with oxygen to produce useable cellular energy.

explanation:

many other transport proteins, often called pumps, move materials against a concentration gradient. active transport drives molecules across a membrane from a region of lower concentration to a region of higher concentration. this process, shown in figure 5.1, uses transport proteins powered by chemi- cal energy.

voluntary muscles are controlled by the cerebellum.