What is immunity ? Explain innate and acquired immunity.
or
What is immunity? Discuss different type of immunity .

Explanation

It is also known as adaptive or specific immunity and supplements the protection provided by innate immunity. Acquired immunity is defined as resistance developed by human beings during their lifetime through exposures to various pathogens. Important features of acquired immunity are
Specificity the ability to distinguish various kinds of foreign entities.
Diversity can recognise a large variety of foreign molecules.
Discrimination between self and foreign molecules can recognise and respond to molecules that are foreign or non-self.

Memory The first encounter with an foreign agent generates an immune response and retains the memory of the encounter. On a second encounter with same agent evokes a heightened immune response.