What is diffusion?

• The movement of a substance from a low concentration to a high concentration.

• The net movement of a substance traveling down its concentration gradient.

• The movement of a substance that requires an input of energy.

• The process where molecules stop moving once equilibrium is reached.

Which statement accurately describes diffusion?

• It is a type of active transport that requires ATP.

• It is a type of passive transport that requires ATP.

• It is a type of active transport that does not require ATP.

• It is a type of passive transport that does not require ATP.

What is facilitated diffusion used for?

• It is used for the transport of LARGE, polar molecules and ions across cell membranes.

• It is used for the active transport of glucose against the concentration gradient.
• It is used for the synthesis of proteins in the cell.
• It is used for the transport of water molecules only.

How does temperature generally affect the rate of diffusion?

• A lower temperature increases the diffusion rate.

• A higher temperature decreases the diffusion rate.

• A higher temperature increases the diffusion rate.

• Temperature has no effect on the diffusion rate.

What happens to the rate of diffusion if the concentration difference of a substance across a barrier increases?

• The diffusion rate decreases.

• The diffusion rate increases.

• The diffusion rate remains the same.

• The substance stops diffusing.