II PUC BIOLOGY MCQ

BODY DEFENSE AND IMMUNITY


1. The ability of an antigen to induce an immune response does NOT depend on the antigen's

a. ability to enter the thyroid.

b. degree of aggregation.

c. dose.

d. size.

e. usual presence in the body.

2. The immune response to a booster vaccine is called a(n)

a. cellular response.

b. humoral response.

c. innate response.

d. primary response.

e. secondary response

3. Lymphocytes are activated by antigen in the
a. blood stream.

b. bone marrow.

c. liver.

d. lymph nodes.

e. skin.

5. Interferons

a. activate B cells to make virus-specific antibodies.

b. are Th2 cytokines.

c. are virus proteins that interfere with activation of cytotoxic T cells.

d. block virus infection of host cells.

e. inhibit virus replication by infected cells.

6. An inflammatory response

a. is characterized by a decrease in vascular permeability.

b. is stimulated by cytokines produced by neutrophils.

c. occurs only during a secondary response.

d. recruits phagocytes to the infection site.

e. usually lasts for many weeks to ensure antigen is completely removed

7. Natural Killer cells

a. are stimulated to kill infected host cells via carbohydrate-binding receptors.

b. kill normal host cells with high levels of membrane MHC Class I.

c. kill virus-infected cells when the virus is acquired naturally but not by immunization.

d . recognize virus-infected cells by the presence of viral peptide on MHC Class II.

e. secrete the complement MAC to lyse virus-infected cells.

8. Which of the following is NOT a characteristic of IgG?

a. It contains 2 g and 2 L chains

b. It crosses the placenta.

c. It is the predominant immunoglobulin in blood, lymph, and peritoneal fluid.

d. It is the largest of all the Igs.

e. Its L chains are either k or l.

9. The plasma from which fibrinogen has been removed is called-

a. Negative plasma b. Serum c. Lymph d. Coelomic-fluid

10. Which one of the following is not a phagocytic cell-

a. Monocyte b. Lymphocyte c. Basophil d. Neutrophil

11.The most numerous leucocytes are-

a. Monocyte b. Eosinophil c. Basophil d. Neutrophil

12. Which statement is not true for non-specific defense of the body-

a.

13. Vaccination protects us from infectious disease by generating memory

a. antigen.

b. lymphocytes.

c. macrophages.

d. PMNs.

e. stem cells.

14. Inflammation does NOT involve

a. cytokine production by macrophages.

b. migration of leukocytes out of the circulation.

c. pain.

d. secretion of antibodies.

e. swelling at the site of infection.

NLX,..,N PLX 15. Jenner observed that milkmaids who were infected with cowpox were later immune to smallpox infections. This is an example of a

a. acquired immunity of barrier skin cells.

b. active immunization with a non-related organism that causes similar symptoms.

c. innate immunity of milkmaids to smallpox.

d. memory response to a cross-reactive antigen.

e. passive immunization from contact with cow's milk antibodies.

16.Which of the following are not true:

a. Ig G crosses the placenta b. thymus gland is responsible for cellular immunity c. C1-9 is used by the alternative complement pathway d. eosinophils are responsible for phagocytosis e. interleukin-1 activates B cells to produce interleukin-2

17.The cells which kill the virus and cancer cells-

a. Killer T cells b. B-lymphocytes c. Antibodies d. Helper T cells

18. Fever is-

a. Third line of defense b. Specific line of defense c. Humoral cell immunity d. Non-specific defense

19. Which statement is not true about urine-

a. It inhibits bacterial growth due to its acidic pH. b. It is a part of specific defense of the body c. It cleanses the lower urinary tract as it flushes out d. It contains isozyme for killing bacteria

20. Which is not an antigen presenting cell –

a. Macrophage b. Langherhans cells c. dendritic cells d. interferons