Question

Select all that apply

Which conditions are necessary for the diffusion of a substance to occur across a membrane?
a concentration gradient
a supply of energy
membrane permeability

Answer 1

a concentration gradient.

membrane permeability.

Step-by-step explanation:

diffusion occurs down a concentration gradient.

and is the free net movement of particles therefore, does not require energy.

membrane permeability is necessary to ensure that the particles can pass through the cell membrane.