DNA has deoxyribose as the constituent sugar. The position where the sugar lacks oxygen is

1. 1

2. 2

3. 3

4. 4

The linkage that joins two adjacent nucleotides in RNA is

1. phosphate ester                 

2. phosphodiester

3. phosphate anhydride         

4. N-glycoside

Phosphodiester bond is present in

1. ATP

2. ADP

3. cAMP

4. none of these

Heating may cause denaturation of enzyme or protein mainly by damaging its

1. physical configuration

2. chemical structure

3. both physical configuration as well as chemical structure

4. other properties.

Which of the following is incorrect?

1. The hair protein, keratin, is synthesized from the amino acid methionine

2. Phospholipids act as carriers of small non polar molecules across the cell membrane

3. Dietary intake of PUFA decreases the serum cholesterol level in our body

4. Cobalt is a constituent of Vit B₁₂

Which of the following vitamins is a coenzyme for amino acid and fatty acid metabolism?

1. Vitamin B₆               

2. Vitamin B₁₂

3. Vitamin B₁               

4. Vitamin B₂

The inhibition of succinic dehydrogenase by malonate is an example of

1. competitive inhibition

2. non-competitive inhibition

3. allosteric modulation

4. none of the above

In RNA thymine is replaced by

1. uracil                           

2. adenine

3. thiamine                       

4. guanine

The vitamin nicotinamide can be synthesized in our body from.

1. tyrosine

2. tryptophan

3. valinc

4. phenylalanine

An example of the competitive inhibition of an enzyme is the inhibition of:

1. succinic dehydrogenase by malonic acid

2. cytochrome oxidase by cyanide

3. hexokinase by glucose -6-phosphate

4. carbonic anhydrase by carbondioxide