Assertion : Activity of an enzyme is pH-dependent.

Reason : Change in pH affects the solubility of the enzyme in water.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.

Cellulose has very high degree of hydrophilicity because of :

• its amorphous nature

• crystalline nature

• presence of excessive voids in solid state

• presence of many hydroxyl groups on the polymer back bone

There are 20 naturally occurring amino acids. The maximum number of tripeptides that can be obtained is :

• 8000

• 6470

• 7465

• 5360

Enzymes are

• fatty acids

• oils

• minerals

• proteins

Which of the following biomolecules contain non-transition metal ion ?

• Vitamin B₁₂

• Chlorophyll

• Haemoglobin

• Insulin

The digestion of fat in intestines is aided by

• emulsification

• peptisation

• protection

• diffusion

An example ofa sulphur containing amino acid is :

• lysine

• serine

• cysteine

• tyrosine

Which of the following is not present in a nucleotide ?

• Cytosine

• Guanine

• Adenine

• Tyrosine

Assertion : Nucleotides are phosphate esters ofnucleosides.

Reason : The various nucleotides in nucleic acids are linked either through purine or pyrimidine bases.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false

• If both assertion and reason are false

By adding sodium dodecyl sulphate, during the electrophoresis of proteins, it is possible to :

• determine a protein's isoelectric point

• determine an enzyme's specific activity

• determine the amino acid composition of the protein

• presence a proteins native structure and biological activity