Question

Could you answer these questions in a simple way?I don't have a good definition of them in my notes thank you!

Membranes: Fluid mosaic model, structure and function of membranes?

​Types of membrane proteins, functions of membrane proteins and examples?

Answer 1

Membranes:

• Fluid mosaic model- In 1972, Singer and Nicolson gave Fluid mosaic model. The model describes cell membrane as quasi fluid, in which protein are found to be inserted in lipid bilayer. It suggests that protein can be mosaic and can be fluid in the lipid bilayer.
• structure

• function of membranes- Protects the cell from harsh conditons and provides a structure and shape to cell. It Demarcates the cell from its surrounding.

Types of membrane proteins, There are broadly two categories - Peripheral and integral proteins.

Peripheral proteins are bound to the membrane membrane by electrostatic and hydrogen bond, most of these proteins are soluble in water.

functions - help in interaction with surrounding water and other molecules.

Examples , peripheral proteins - Spectrin and Ankyrin, it helps determine the shape and flexibilty of RBC.

Integral proteins- These are help in lipid bilayer very tighly . Integral proteins can have one or more segment embedded in the bilayer, these are called transmembrane protein.