Question

2 which of the following is a feature that distinguishes active transport from facilitated diffusion? multiple choice saturation of transport rate requirement for a carrier molecule carrier molecules have specificity presence of a transport maximum requirement for metabolic energy

Explanation:

Active transport moves substances against their concentration gradient and requires metabolic energy (such as ATP), while facilitated diffusion moves substances down their concentration gradient and does not require metabolic energy. The other options (saturation of transport rate, requirement for a carrier molecule, carrier - molecule specificity, presence of a transport maximum) are features that can be common to both active transport and facilitated diffusion.

Answer:

E. Requirement for metabolic energy