(B) What are the different defense mechanisms operating in our body? Briefly discuss the types of non specific defense mechanism.

ANS- In a general sense, we can think of our defenses as consisting of three types.

• General, Non-specific (barriers and chemical defenses, such as skin and stomach acid)
• Non-specific recognition of certain molecular shapes on pathogens (the innate immune system)
• Highly specific (the acquired or adaptive immune system, which involves highly specific recognition of particular molecular shapes on pathogens and the ability to make highly specific antibodies to aid in the remove of specific pathogens)

The body possesses many mechanisms that impart nonspecific defense. The objectives of these mechanisms are to prevent microorganisms from gaining a foothold in the body and to destroy them if they penetrate to the deeper tissues.