Biomolecules (Biology) · Question 43

Which of the following statements is correct with reference to enzymes?

1. Holoenzyme = Apoenzyme + Coenzyme
2. Coenzyme = Apoenzyme + Holoenzyme
3. Holoenzyme = Coenzyme + Co-factor
4. Apoenzyme = Holoenzyme + Coenzyme

Which of the following are not polymeric?

1. Proteins
2. Polysaccharides
3. Lipids
4. Nucleic acids

A typical fat molecule is made up of

1. one glycerol and one fatty acid molecule
2. three glycerol and three fatty acid molecules
3. three glycerol molecules and one fatty acid molecule
4. one glycerol and three fatty acid molecules.

Which one of the following statements is wrong?

1. Uracil is a pyrimidine.
2. Glycine is a sulphur containing amino acid.
3. Sucrose is a disaccharide.
4. Cellulose is a polysaccharide.

A non-proteinaceous enzyme is

1. lysozyme
2. ribozyme
3. ligase
4. deoxyribonuclease.

Which of the following is the least likely to be involved in establishing the three-dimensional folding of most proteins?

1. Hydrogen bonds
2. Electrostatic interaction
3. Hydrophobic interaction
4. Ester bonds

Which of the following describes the given graph correctly? [figure]

1. Endothermic reaction with energy A in presence of enzyme and B in absence of enzyme.
2. Exothermic reaction with energy A in presence of enzyme and B in absence of enzyme.
3. Endothermic reaction with energy A in absence of enzyme and B in presence of enzyme.
4. Exothermic reaction with energy A in absence of enzyme and B in presence of enzyme.

The chitinous exoskeleton of arthropods is formed by the polymerisation of

1. N-acetyl glucosamine
2. lipoglycans
3. keratin sulphate and chondroitin sulphate
4. D-glucosamine.

Which of the following biomolecules does have a phosphodiester bond?

1. Amino acids in a polypeptide
2. Nucleotides in a nucleic acid
3. Fatty acids in a diglyceride
4. Monosaccharides in a polysaccharide

Which one of the following statements is incorrect?

1. The competitive inhibitor does not affect the rate of breakdown of the enzyme-substrate complex.
2. The presence of the competitive inhibitor decreases the Km of the enzyme for the substrate.
3. A competitive inhibitor reacts reversibly with the enzyme to form an enzyme-inhibitor complex.
4. In competitive inhibition, the inhibitor molecule is not chemically changed by the enzyme.