Which set is the correct pairing set (or contains complementary pairs) responsible for the structure of DNA ? (A-adenine, G-guanine, C-cytosine, T-thymine, U-uracil)

• A-T, G-C

• A-C, G-T

• A-G, C-T

• A-U, G-C

α-helix is found in :

• DNA

• RNA

• Lipid

• Protein

Raffinose is

• trisaccharide

• disaccharide

• monosaccharide

• polysaccharide

Lactic acid molecule has

• one chiral carbon atom

• two carbon atoms less

• three carbon atoms less

• asymmetric molecule

The metal ion present in vitamin B₁₂ is

• Co³⁺

• Co²⁺

• Fe²⁺

• Fe³⁺

Glucose on oxidation gives the acid containing the C-chiral atoms equal to

• 2

• 3

• 4

• 5

Which of the following is not correct?

• Chlorophyll is responsible for the synthesis of carbohydrates in plants

• The compound formed in the addition of oxygen to haemoglobin is called oxyhaemoglobin.

• Acetyl salicylic acid is known as aspirin.

• The metal ion present in vitamin B₁₂ is Mg²⁺

For a reversible reaction, A $\rightleftharpoons$ B, which one of the following statements is wrong from the given energy profile diagram?

• Activation energy of forward reaction is greater than backward reaction

• The forward reaction is endothermic.

• The threshold energy is less than that of activation energy.

• The energy of activation of forward reaction is equal to the sum of heat of reaction and the energy of activation of backward reaction.

Hydrolysis of sucrose with dilute aqueous sulphuric acid yields-

• 1 : 1 D-(+)-glucose; D-(-)-fructose

• 1 : 2 D-(+)-glucose; D-(-)-fructose

• 1 : 1 D-(-)-glucose; D-(+)-fructose

• 1 : 2 D-(-)-glucose; D-(+)-fructose

90.

Which of the following biomolecules acts as specific catalysts in biological reaction ?

• Carbohydrates

• Lipids

• Vitamins

• Enzyme