Question

in which process(es) do carrier molecules transport materials against a concentration gradient?
answer
osmosis
facilitated diffusion
diffusion
active transport
i dont know yet

Explanation:

• Osmosis: Movement of water down concentration gradient, no carrier, passive.
• Facilitated diffusion: Molecules move down gradient via carriers, passive.
• Diffusion: Molecules move down gradient, no carrier, passive.
• Active transport: Uses carriers to move molecules against gradient, requires energy.

Answer:

D. Active transport