Biochemistry

I will be uploading a few interesting articles which the students may find useful.  Feedback / suggestions/ questions are welcome from students. Please find the answers to the immunology test conducted below.

                                                               M.Sc. Part II (Semester – III) Examination, 2014

Biochemistry / Environmental Biotechnology ( Paper –XI)

 

Immunochemistry

 

Day & Date : 02/08/2014                                                             Total Marks : 10

Time : 1.00 p.m.                                                                            Internal Test – 1

1.  Which class of antibodies is found in the primary immune response and why?

 

            IgM because Mew is the first constant region on the DNA

 

2. Where are B lymphocytes synthesized and where do they mature?

 

            Synthesized and mature in bone marrow

 

3. What happens in the secondary follicle (germinal centre) in the lymph node?

 

            T-B conjugate formation leading to activation of B lymphocyte

 

4.  Name any two receptors for recognizing microbial patterns in innate immunity.

 

            Toll like receptors, Mannan binding receptors, C3b receptors

 

5.  Give two major differences between innate and adaptive immunity.

            Innate : Always present, limited or group specificity, No memory

            Adaptive: Induced, absolute specificity, Memory developed

 

6. What is the function of RAG 1 and RAG 2 gene product?

 

            Helps in joining of VDJ region to form the antigen binding site

 

7. Outline Susunma Tonegawa’ experiment – what did he conclude?

           

            Used embryonic and mature B lymphocytes, lysed them, isolated DNA, treated them with restriction endonucleases, subjected to electrophoresis and Southern blot using labeled mRNA of Ab. Found single band for adult cell and two bands for embryonic cell Concluded that variable and constant regions are apart in embryonic cells and together in adult cell. (Proving presence of multiple V segments)

 

8. What is the function of neutrophils?

 

            Phagocytic cells – first to reach site of infection , initiate inflammatory response

 

9. What is the purpose of allelic exclusion?   

           

            To generate a B lymphocyte with one and one specificity only

 

10. Depict the primary RNA transcript when V27 combines with D3 and J4 (totally there are

      35V segments , 27 D segments and 6 J segment)

 

      Leader – V27-D3-J4-J5-J6-Cmew-Cdelta