Which of the following statements about active transport is true? Molecules move down the concentration gradient.

ATP is not required to move molecules through the membrane.

ATP is formed as molecules pass through protein channels.

It results in a higher concentration of molecules on one side of the membrane.

It results in a higher concentration of molecules on one side of the membrane.

Explanation:

Active transport is the transport of molecules up the concentration gradient. This means that molecules are going from low density to high density. This is the opposite of natural diffusion. So, it requires ATP to move the molecules this way. Diffusion normally occurs to maintain homeostasis and an equal amount of concentration on both sides of a membrane. But, with active transport, since molecules are moving up the gradient, the opposite happens and the concentrations are unequal.

thermophiles, notice the prefix thermo.