Define immunity. Discuss its types.

Define permeability. Give its types.

Define the term collision. Discuss its types with examples.

Define immunity. Write about the cells of immune system. Name two types of immune systems of body.

Define immunity. Describe different ways to develop immunity. Write two differences between active and passive immunity.

Define biodiversity. Discuss the causes of extinction of biodiversity.

Define cybrid. Discuss the mechanism of its production.