KE REVIEW ~ UNIT 4

Front

What is the primary function of proteins embedded in the plasma membrane?

Back

They selectively allow certain particles into and out of the cell.

Front

What component of the plasma membrane acts as the primary barrier to most foreign substances?

Back

Phospholipid bilayer.

Front

What type of cellular transport requires energy from the cell?

Back

Active transport.

Front

What is the function of the CH2 and phosphate molecular structure in the plasma membrane?

Back

It allows a cell to regulate the movement of materials into and out of a cell.

Front

How does facilitated diffusion differ from simple diffusion?

Back

Facilitated diffusion requires membrane proteins.

Front

Define 'plasma membrane'.

Back

A biological membrane that separates and protects the interior of all cells from the outside environment.

Front

What is the role of cholesterol in the plasma membrane?

Back

Cholesterol helps to stabilize the membrane's fluidity.

Front

What is diffusion?

Back

The movement of particles from an area of higher concentration to an area of lower concentration.

Front

What is osmosis?

Back

The diffusion of water across a selectively permeable membrane.

Front

What is active transport?

Back

The movement of molecules across a membrane from a region of lower concentration to a region of higher concentration, requiring energy.