Structure and function are correlatable in living organisms.

• Taking a look at the structure of RBCs-

It is called biconcave shape. The function of RBCs is to pass through capillaries and carry more oxygen and this shape helps it to absorb more oxygen.

• Taking a look at the structure of plasma membrane –

It is made up of proteins, carbohydrates and lipids. The lipids arranged with their hydrophilic polar head directed outwards and non-polar hydrophobic tails directed inwards providing fluidity to the membrane. This provides the cell membrane its selective permeability.