Complete the sentence using one of the following words: Starch, Glycogen, or Cellulose.
is a carbohydrate that makes up the cell walls of
plants.

i was thinking 4.0 v hope this

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.