Which is not a poison for enzymes?

(1) CN^-                       

(2) Fe³⁺

(3) Pb²⁺                     

(4) ${\mathrm{AsO}}_4^{3-}$

The non-proteinous substances which certain enzymes required for their activity are called:

(1) catalysts                     

(2) inhibitors

(3) co-enzymes                 

(4) epimers

The complementary base of adenine in one strand to that in the other strand of DNA is:

1. Cytosine

2. Guanine

3. Uracil

4. Thymine

Antibodies are?

(1) Carbohydrates

(2) proteins

(3) phospholipids

(4) lipids

Which of the following statements about enzymes is incorrect?

(1) The catalytic action of an enzyme is not specific

(2) An enzymatic reaction is highly sensitive to temperature

(3) The catalytic action of enzymes is due to their capacity to lower the energy of activation of a particular reaction

(4) None of the above

Redness of blood is because of the presence of:

(1) iron in heme pigment

(2) haemoglobin

(3) copper in heme pigment

(4) all of the above

An antigen develops antibodies which protect the body from their harmful effects. The antibodies
are:-

(1) immunoglobulins

(2) phospholipids

(3) albumins

(4) lymphocytes

Which one is a test for proteins?

(1) Beilstein test             

(2) Biuret test

(3) Benedict's test           

(4) Molisch test

Insulin has 51 amino acids in two polypeptide chains which are linked by:

(1) one sulphide bond

(2) one disulphide bond

(3) two disulphide bonds

(4) three disulphide bonds

(1) B

(2) C

(3) D

(4) E