Question

2. Which of the following is NOT correct with regard to the MCH I presentation complex?

a. It can bind the CD8 conplex

b. It is loaded with antigen inside the phagolysosome

c. It can present antigens to cytotoxic T cells

3. which type of immune system cell is responsible for activating cyctotoxic T cells?

a. Th2

b. Natural Killer Cells

c. Plasma Cells

d. Th1

Answer 1

SOLUTION-

2. Which of the following is NOT correct with regard to the MCH I presentation complex?

a. It can bind the CD8 conplex

b. It is loaded with antigen inside the phagolysosome

c. It can present antigens to cytotoxic T cells

Solution-

Let’s explain the first option- Yes, MCH actually MHC (Major Histocompatibility Complex) can bind with CD8 receptor through interaction of α-3 receptor of plasma membrane and CD8 of T-cell. This α3- CD8 interaction holds MHC-I and check antigenecity.

Option-b- This option is right for the MHC-II not for MHC-I, because dendritic cell fuse and phagocytoses bacterial cell and attach with phagosome and lysosome to destroy bacteria. Whereas in infected cell antigens specific to the pathogen processed in the proteasomes and presented to cytotoxic T-cell through MHC-I. So, this option is not correct.

Option-c- It is obvious and normal function of MHC-I that specific antigen present to cytotoxic T-cell to destroy the antigen.

3. which type of immune system cell is responsible for activating cyctotoxic T cells?

a. Th2

b. Natural Killer Cells

c. Plasma Cells

d. Th1

Solution-

          Correct answer is option-d. Th1 (Helper T Cell-I) it is the part of cellular immune system which helps to proliferate cytotoxic CD8 T cell to enhance killing power.

          Option- a TH2 (Helper T Cell-2) involved in hormonal immunity stimulates- B cell.

          Option- b. NK cell activated through the activation of antigen presenting cell (APC) same as cyctotoxic T cells.

         Option –c Plasma Cells secrets high level of immune globulins (Antibody).