State whether the following statements is true/false regarding DNA replication.

1. The polymerization of DNA is essentially irreversible due to the hydrolysis of pyrophosphate.

2. On average about twenty errors are made during each replication of the human genome.

3. DNA polymerase I possesses 5ʹ → 3ʹ exonuclease activity.

4. All DNA ligase enzymes use ATP as a cosubstrate.

5. The purpose of SSB is to prevent single-stranded DNA from folding back on itself to form double-helical regions.

#Question id: 858

#Unit 1. Structure and Function of Biomolecules

Unfolded protein response (UPR)

#Question id: 859

#Unit 1. Structure and Function of Biomolecules

Which one statement is incorrect about ATG genes;

#Question id: 860

#Unit 1. Structure and Function of Biomolecules

Select true ‘T’ AND false ‘F’ about ubiquitinylation

I. These ubiquitin-like modifiers control processes as diverse as nuclear import,

II. Regulated by the ubiquitin-like modifier Sumo, and autophagy,

III. Regulated by the ubiquitin-like modifier Atg8.

IV. For a protein to be efficiently degraded, it must be linked to a chain of at least four tandemly linked ubiquitin molecules in which Lys 34 of each ubiquitin forms an isopeptide bond with the C-terminal carboxyl group of the following ubiquitin.

#Question id: 861

#Unit 1. Structure and Function of Biomolecules

Alexander Varshavsky discovered, the half-lives of many cytoplasmic proteins vary with the identities of their N-terminal residues via the so-called N-end rule:-

#Question id: 862

#Unit 1. Structure and Function of Biomolecules

Match the following

#Question id: 863

#Unit 1. Structure and Function of Biomolecules

Ubiquitinated proteins are proteolytically degraded in an ATP-dependent process mediated by a large (∼2500 kD, 26S) multiprotein complex named the 26S proteasome;