Recognition and digestion by the phagocytes due to the coated surface of antigens by the antibodies is known as

Which of the following are included as cellular barriers in innate immunity?

Which cells are responsible for active acquired immunity?

Which of the following is not a component of innate immunity?

Which of the following statements are correct regarding the structure and types of antibodies in humans?
$i$. Antibodies are also called Immunoglobulins that are produced as an immune response to antigenic stimulation.
$ii$. They are produced by all types of $T$-lymphocytes and $B$-lymphocytes.
$iii$. An antibody is a $Y$-shaped molecule formed of four polypeptide chains. Antibodies present in plasma determine many blood group systems like $ABO$,$Rh$,$P$,$MNS$ etc.
$iv$. An antibody molecule consists of two antigen-binding sites called paratopes.

Define the following terms: Pathogen and Immunity.