Question

if the sugar concentration in a cell is 3% and the concentration in the cells environment is 5%, how can the cell obtain more sugar? hint: sugar is polar and does not pass through the phospholipid bilayer easily. a. sugar can diffuse straight through the phospholipid bilayer. b. sugar can undergo facilitated diffusion through a channel protein and no energy is required. c. the cell cannot obtain any more sugar. it is doomed. d. the cell must use active transport to pump the sugar in. energy is required.

Explanation:

Sugar is polar and has a higher concentration outside the cell (5%) compared to inside (3%). Facilitated diffusion moves substances from high - to low - concentration through channel or carrier proteins without energy. Since sugar is polar and the concentration gradient is from outside to inside, it can use facilitated diffusion through a carrier protein (not a channel protein as channel proteins are mainly for ions). Option A is wrong as sugar cannot diffuse through the phospholipid bilayer easily. Option C is an over - statement. Option D is incorrect as active transport is for moving substances against the concentration gradient and energy is not required for this situation.

Answer:

B. Sugar can undergo facilitated diffusion through a carrier protein and no energy is required.