Question

1. which process requires energy?

a. diffusion
b. passive transport
c. osmosis
d. active transport

Explanation:

• Diffusion (a) is the movement of particles from high to low concentration, no energy needed.
• Passive transport (b) (including diffusion and osmosis) moves substances down concentration gradients, no energy.
• Osmosis (c) is the diffusion of water, also passive, no energy.
• Active transport (d) moves substances against concentration gradients, which requires energy (e.g., ATP).

Answer:

d. active transport