The couplings between base units of DNA is through : 

1.	Hydrogen bonding	2.	Electrostatic bonding
3.	Covalent bonding	4.	Van der waal's forces

The segment of DNA which acts as the instrumental manual for the synthesis of the protein is 

1. nucleotide

2. ribose

3. gene

4. nucleoside

Which of the following structures represents the peptide chain ?

1. 

2. 

3. 

4. 

On hydrolysis of starch, we finally get

1. glucose

2. fructose

3. Maltose

4. Both 1 and 3

The correct option about the presence of  H-bond in nucleotides is: 

1. A-T, G-C

2. A-G, T-C

3. G-T, A-C

4. A-A, T-T

The helical structure of proteins is established by

1. dipeptide bonds

2. hydrogen bonds

3. ether bonds

4. peptide bonds

The a-D-glucose and b-D-glucose differ from each other due to difference in carbon atom with respect to its

1. conformation

2. configuration

3. number of OH-groups

4. size of hemiacetal ring

Glycolysis is

1. oxidation of glucose to pyruvate

2. conversion of glucose to haem

3. oxidation of glucose to glutamate

4. conversion of pyruvate to citrate

Sucrose in water is dextrorotatory, ${\left[\mathrm{\alpha }\right]}_D=+66.4°$ when boiled with dil.HCl, the solution becomes leavorotatory, ${\left[\alpha \right]}_D=-39.9°.$ In this process the sucrose breaks into

1. L-glucose + D-fructose

2. L-glucose + L-fructose

3. D-glucose + D-fructose

4. D-glucose + L-fructose

Which is not a true statement?

1. a-carbon of a-amino acid is asymmetric except glycine

2. All proteins are found in L-form

3. Human body can synthesis all proteins they need

4. At pH = 7 both amino and carboxylic groups exist in ionised form