Leonidas Flowers

Biology

5 January, 18:50

Active transport requires energy because it usually involves the movement of

A.

substances from an area of low concentration to an area of high concentration.

B.

substances from an area of high concentration to an area of low concentration.

C.

substances in the gas phase, such as oxygen and carbon dioxide.

D.

substances that can easily pass through the cell membrane, such as water.