Chapter 23.3, Problem 16SSC

Interpretation Introduction

Interpretation:

The structure and function of cell membranes should be described.

Concept introduction:

A biological membrane which separates the cell from inside as well as from the outside environment and this cell membrane protects the cell from its surrounding is known as cell membrane.

Explanation of Solution

The membrane which protects the cell from its surrounding is known as cell membrane. The cell membrane consists of a phospholipid bilayer which is arranged in back to back way. The membrane also covered with cholesterol and proteins in some places. Cell membrane consists of large amount of proteins that is 50 % of volume of membrane. Proteins are important for the cell as they help in biological activity in the cell. Cell membrane contains membrane proteins and integral proteins which act as membrane transporters. Cell membrane also contains peripheral proteins that are loosely linked with an outer side of the cell membrane that acts as enzymes shaping the cell. The membrane controls the movement of substances inside and outside of the cell. It also consists of carbohydrates which play important role in cell-cell recognition.

The functions of cell membrane are:

1. Cell membrane protects the cell from its environment.
2. Cell membrane also regulates the transport of substance inside and outside of the cell.
3. Cell membrane acts as a receptor.
4. Cell membrane acts as a messenger which receives messages from the cell.
5. Cell membrane transport materials which are needed for survival. This can be active or passive (osmosis).