Biochemistry

• - is a/an example of a structural protein which is also an enzyme.

• Actin

• Myosin

• Trypsin

• Troponin

Glucose and mannose are epimers. This means that?

• They are mirror images of each other

• One is an aldose, the other a ketose

• They rotate plane polarized light in opposite directions

• They differ only in the configuration of one carbon atom

The forces that maintain the three dimensional structure of a protein is_________

• Non-covalent

• Covalent

• Coordinate

• Covalent and non covalent

Thermal denaturation of protein involves

• Conformational change in the protein

• Random cleavage of the peptide bonds

• Covalent modification of certain amino acids

• Increase in its isoelectric point

What is the molecular mass of a tri-peptide if the molecular mass of an amino acid is 150 Daltons?

If one needs to use the natural 20 amino acid residues, with no restrictions on the number of times a given residue type can be used, what is the total no of possible tripeptide sequences?

• 20x3

• 20x 19x 18

• 4000

• 8000

With all L-amino acids, the mirror image of right-handed alpha-helix will appear as

• Left-handed alpha -helix with L-amino acids

• Left-handed alpha -helix with D-amino acids

• Right-handed alpha -helix with L-amino acids

• Right-handed alpha -helix with D-amino acids

The folding pathway of protein requires an enzyme that catalyzes the interchange or shuffling of disulphide bonds____

A peptide bond

• has partial double bond character

• is ionized at physiological pH

• is stable to heating in strong acids

• occurs most commonly in the cis-configuration

Which of the following amino acids is most compatible with an alpha-helical structure?

• Proline

• Histidine

• Alanine

• Glycine