Cell Transport

What is the main job of the cell membrane?

• To produce energy for the cell.

• To store genetic material.

• To control what enters and leaves the cell.

• To break down waste products.

Which statement best describes simple diffusion?

• It requires energy to move molecules.

• It moves molecules from an area of low concentration to high concentration.

• It allows small, non-polar molecules to pass directly through the cell membrane without energy.

• It uses protein channels to help molecules cross the membrane.

How does facilitated diffusion help molecules cross the cell membrane?

• It uses ATP energy to pump molecules against their concentration gradient.

• It allows large or polar molecules to pass through with the help of transport proteins.

• It only allows water molecules to pass through the membrane.

• It involves the cell engulfing substances to bring them inside.

What is a key characteristic of active transport?

• It moves molecules from a high concentration to a low concentration.

• It does not require any energy.

• It moves molecules against their concentration gradient and requires energy.

• It only transports small, non-polar molecules.