Membrane Structure

Question 1

Describe the fluid-mosaic model of the cell membrane.

Answer 1

• Cell membrane is composed of a bi-layer of phospholipids with proteins and other macromolecules embedded.
• The membrane is dynamic (constantly changing) – the phospholipids and proteins are able to move about within the membrane, in a fluid-like manner.
• The proteins embedded give the membrane a mosaic-like appearance.

Question 2

Describe one function of the proteins embedded in the cell membrane.

Answer 2

• Transport proteins – enable the movement of molecules across the membrane (into and out of the cell).
• Membrane receptors – allow cell-cell communication (e.g. hormone receptors in the membrane allow hormones to bind, triggering an effect in the cell).