Antiparallel strands of a DNA molecule means that

1. The phosphate groups of two DNA strands, at their ends, share the same position

2. The phosphate groups at the start of two DNA strands are in opposite position (pole)

3. One strand turns clockwise

4. One strand turns anti-clockwise 

In the DNA molecule

1. The total amount of purine nucleotides and pyrimidine nucleotides is not always equal

2. There are two strands which run parallel in 5'$\to$3' direction

3. The proportion of adenine in relation to thymine varies with the organism

4. There are two strands which run antiparallel one in 5'$\to$3' direction and other in 3'$\to$5' direction 

Select the option which is not correct with respect to enzyme action.

1. Substrate binds with enzyme as its active site

2. Addition of lot of succinate does not reverse the inhibition of succinic dehydogenase by malonate.

3. A non-competitive inhibitor binds the enzyme at a site distinct from that which binds the substrate

4. Malonate is a competitive inhibitor of succinic dehydrogenase

Transition state structure of the substrate formed during an enzymatic reaction is

1. Transient but stable

2. Permanent but unstable

3. Transient but unstable

4. Permanent and stable

Which of the following statements regarding enzyme inhibition is correct?

1. Competitive inhibition is seen when a substrate competes with an enzyme for binding to an inhibitor protein

2. Competitive inhibition is seen when the substrate and the inhibitor compete for the active site on the enzyme

3. Non-competitive inhibition of an enzyme can be overcome by adding large amount of substrate

4. Non-competitive inhibitors often bind to the enzyme irreversibly 

One turn of the helix in a B-form DNA is approximately

1. 0.34 nm

2. 3.4 nm

3. 2 nm

4. 20 nm

In amino acid is a

1. Substituted methane

2. Substituted ethane

3. Any acid having amino group

4. Derivative of indoacetic acid

About 98% of the mass of every living organism is composed of just six elements including carbon, hydrogen, nitrogen, oxygen and:

(1) Phosphorous and sulphur

(2) Sulphur and magnesium

(3) Magnesium and sodium

(4) Calcium and phosphorous

In non-competitive inhibition:

1. the substrate and inhibitor cannot bind to the enzyme at the same time

2. the inhibitor binds only to the substrate-enzyme complex

3. the inhibitor can bind to the enzyme at the same time as the enzyme's substrate

4. the binding of the inhibitor to the enzyme reduces its activity but does not affect the binding of substrate

G.N. Ramachandran discovered the structure of collagen which is a/an:

1. Alpha helix

2. Beta pleated sheet

3. Triple helix

4. Icosahederon