MALT constitutes about ___ percent of the lymphoid tissue in human body. [2017]
20%
70%
10%
50%
(4)
MALT are significant aggregations of lymphoid tissues which are seen in relation to the mucosa of the major tracts like respiratory, alimentary canal and urinogenital tracts. It constitutes about 50 percent of the lymphoid tissue in human body.
Antivenom injection contains preformed antibodies while polio drops that are administered into the body contain: [2016]
gamma globulin
attenuated pathogens
activated pathogens
harvested antibodies
(2)
The Sabin vaccine or trivalent ‘oral polio vaccine’ consists of attenuated viral strains.
In higher vertebrates, the immune system can distinguish self-cells and non-self. If this property is lost due to genetic abnormality and it attacks self-cells, then it leads to: [2016]
autoimmune disease
active immunity
allergic response
graft rejection
(1)
Autoimmunity is a disorder of the body’s defence mechanisms in which an immune response is elicited against its own tissues, which are thereby damaged or destroyed. Autoimmunity may be caused due to genetic or environmental factors.
If you suspect major deficiency of antibodies in a person, to which of the following would you look for confirmatory evidence? [2015, 2007]
Haemocytes
Serum globulins
Fibrinogen in plasma
Serum albumins
(2)
Serum globulins are proteins that include gamma globulins (antibodies) and a variety of enzymes and carrier/transport proteins.
The specific profile of the globulins is determined by protein electrophoresis (SPEP), which separates the proteins according to size and charge. There are four major groups that can be identified: alpha-1 globulins, alpha-2 globulins, beta globulins, and gamma globulins. Once the abnormal group has been identified, further studies can determine the specific protein excess or deficit. Since the gamma fraction usually makes up the largest portion of the globulins, therefore antibody deficiency is mainly related with the low level of serum globulins.
Which of the following immunoglobulins does constitute the largest percentage in human milk? [2015]
IgA
IgG
IgD
IgM
(1)
IgA immunoglobulins are the second most abundant class of immunoglobulins, which are mainly found in sweat, tears, saliva, mucus, colostrum and gastrointestinal secretions.
Grafted kidney may be rejected in a patient due to: [2015]
passive immune response
innate immune response
humoral immune response
cell-mediated immune response
(4)
Cell-mediated immune response (CMIS) consists of T-lymphocytes. It reacts against transplants. Transplantation may result in the rejection of the transplanted organs. The immune system recognises the protein in the transplanted tissue or organ as foreign and initiates cellular immunity against it.
Identify the statement that is NOT correct. [2025]
Each antibody has two light and two heavy chains.
The heavy and light chains are held together by disulfide bonds.
Antigen binding site is located at C-terminal region of antibody molecules.
Constant region of heavy and light chains are located at C-terminus of antibody molecules
(3)
Each antibody molecule has four peptide chains, two small called light chains and two longer called heavy chains. Hence, an antibody is represented as .
In an antibody molecule, antigen binding site is located at N-terminal region.
After maturation, in primary lymphoid organs, the lymphocytes migrate for interaction with antigens to secondary lymphoid organ(s) / tissue(s) like
A. thymus
B. bone marrow
C. spleen
D. lymph nodes
E. Peyer’s patches
Choose the correct answer from the options given below [2025]
B, C, D only
A, B, C only
E, A, B only
C, D, E only
(4)
The primary lymphoid organs are bone marrow and thymus where immature lymphocytes differentiate into antigen-sensitive lymphocytes.
After maturation, the lymphocytes migrate into secondary lymphoid organs like spleen, lymph nodes, Peyer’s patches of small intestine and appendix.
These secondary lymphoid organ provide the sites for interaction of lymphocytes with the antigen.
Which of the following type of immunity is present at the time of birth and is a non-specific type of defence in the human body? [2025]
Acquired Immunity
Innate Immunity
Cell-mediated Immunity
Humoral Immunity
(2)
Innate immunity is non-specific type of defence, that is present at the time of birth. This is accomplished by providing different types of barriers to the entry of the foreign agents into our body. Acquired immunity is pathogen specific, characterised by memory cells.
Immune response mediated by B-lymphocytes is humoral immunity and other immune response mediated by T-lymphocytes is called cell-mediated immunity.
