Spectrum Biology - September 2016

H MAN HEALTH & D SEASES

Directions (Q. Nos. 1-50) These questions consist of two statements, each printed as Assertion and Reason.

While answering these questions you are required to choose any one of the following five responses.

(a) Both Assertion and Reason are true and Reason is the correct explanation of Assertion.

(b) Both Assertion and Reason are true, but Reason is not the correct explanation of Assertion.

(c) Assertion is true, but Reason is false.

(d) Both Assertion and Reason are false.

(e) Assertion is false, but Reason is True.

1. As ser tion Sickle cell anaemia is a congenital

disease.

Rea son In congenital diseases anatomical or

physiological abnormalities are present from birth.

2. As ser tion Endotoxins are retained in the

bacterial cells and released when bacteria die and

disintegrate.

Reason The diseases brought about by endotoxins

include dysentery, cholera, typhoid fever and

bubonic plague.

3. As ser tion The complement system is a group of

over 30 proteins. Many of which are enzyme

precursors and are produced by the pituitary gland.

Reason These proteins are present in the blood

plasma and on plasma membranes.

4. As ser tion Asthma patients feel difficulty in

breathing.

Reason The tissue surrounding the bronchioles of

the lungs swell up and compresses the bronchioles.

5. As ser tion Ra di a tion ther apy in volves the

ex po sure of the can cer ous parts of the body to

γ-rays.

Reason Isotopes of radon (Rn-220), cobalt (Co-60)

and iodine (I-131) are used for this purpose.

6. As ser tion The Major Histocompatibility

Complexes (MHCs) are responsible for lymphocyte

recognition and antigen presentation.

Reason It is encoded by several genes located on

human chromosome 7.

7. As ser tion Leukemias are commonly called blood

cancers.

Rea son Leukemias are characterised by abnormal

increase of white blood corpuscles.

8. As ser tion Epitopes are components of antigen and
   each antigen carries a single epitope.

Reason An antibody can bind to only a single

epitope at a time.

9. As ser tion Dendritic cells are Antigen Presenting
   Cells (APCs) characterised by long cytoplasmic

processes.

Reason Dendritic cells are found in lymph nodes,

spleen, thymus as well as in the skin and are

phagocytic in nature.

10.As ser tion The genome of HIV consists of a single

stranded RNA filament segmented into two

identical filaments.

Reason The envelope of HIV possesses a lipid

bilayer derived from host cell membrane.