A phospholipid is a common type of lipid molecule that is hydrophilic at one end and hydrophobic at the other. Explain how this structural characteristic of a phospholipid contributes to the formation of plasma membranes.

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.

above statement is not a true statement about the open ocean because the open ocean has low levels of nutrients. most of the photosynthetic activity on earth occurs in the open ocean within the photic zone. organisms in the deep ocean are exposed to frigid temperatures and total darkness but it does not begin at the low-tide mark.

ok yes, but what is the question? as soon as you ask the actual question i will answer it. : )