Question

1- Immunodeficiency is a general term that refers to the loss of:
	A functional mast cells in the body. B immune system function because of genetic mutations. C one or more components of the immune system. D immune system function with age.

2- How does a vaccination help to prevent a disease?
	A It generates a population of plasma cells that increase the concentration of antibody in the bloodstream. B It generates a population of memory cells that speed up the response to an actual infection. C It establishes defenses that prevent a pathogen from entering the body. D It reduces the severity of symptoms to a disease.

3- Antibodies are formed by which cells of the immune system?
	A phagocytes B B cells C T cells D natural killer cells E mast cells

Answer 1

1. Ans- C. One or more components of the immune system.

Primary immunodeficiency	Secondary immunodeficiency
Predominant antibody defect	systemic disorder-diabetis, HIV
Combined B and T cell defect	prolonged serious illness.
Complement defect
Phagocytic defect

2. Ans .B.It generates a population of memory cells that speed up the response to an actual infection.

Vaccine is composed of dead or heat killed Organism that doesn't cause infection but immune system detect them as enemy and produce antibodies. After passing of threat, though the antibody will be denatured but the memory cells will persist.

Next time when this antigen will encounter, memory cells automatically activated and started producing Antibody quickly to damaged the antigen.

3. Ans . B. B cells

Antibodies are produced by specialized white blood cell called as B lymphocytes or B cells.