Classifying thing about observation can be best done by using a

answer: that would be cheating

explanation:

human didn't come from monkeys man i hate these stupid teachers

this is a good question! i'll do some research and come back when i have the answer!

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.