Question

what are two main differences between passive transport and active transport?

Explanation:

Active transport requires energy (ATP) to move substances against their concentration gradient, while passive transport does not require energy and moves substances along their concentration gradient. Also, active transport often uses carrier - proteins that can change shape, and passive transport can involve simple diffusion, facilitated diffusion (using channel or carrier proteins) or osmosis.

Answer:

1. Energy requirement: Active transport needs energy (ATP), passive transport does not.
2. Concentration gradient: Active transport moves substances against the concentration gradient, passive transport moves substances along the concentration gradient.