Xeroderma pigmentosum is produced as a result of a defect in:

A. DNA polymerase III

B. DNA polymerase I

*C. DNA exonuclease

D. DNA polymerase II

E. DNA ligase

One of the following mutations is potentially lethal. Point out it:

A. Substitution of methylcytosine for cytosine

B. Substitution of adenine for cytosine

*C. Insertion of one base

D. Transvertion

E. Substitution of guanine for cytosine

Which of the following is not a post transcriptional modification of RNA?

A. 3’-polyadenylation

B. None of the above

*C. Glycosylation

D. 5’-capping

E. Splicing

Which one of the following is the function of small nuclear ribonucleoprotein particles (SnRNP)?

A. Termination of protein synthesis

B. Replication of DNA

*C. Processing of RNA

D. Activation of amino acids

E. Initiation of protein synthesis

In mammals, dna synthesis occurs in which part of the cell cycle:

A. G0 phase

B. M phase

C. G2 phase

D. G1 phase

*E. S phase

Transcription is inhibited by:

A. Chloramphenicol

B. Streptomycin

C. Sulfonylamide

*D. Amanitin

E. Puromycin

What does restriction endonuclease cleave?

A. Polypeptide

*B. Double stranded DNA

C. Single stranded DNA

D. Single stranded RNA

E. Nucleoside

Choose the main place for r-RNA production:

A. Ribosome

B. Endoplasmic reticulum

*C. Nucleolus

D. Nucleus

E. Cytoplasm

Poly (A) tail of eukaryotic m-RNA is translated into:

A. Polyglycine

*B. Polylysine

C. Polymethionine

D. Polyproline

E. Polyalanine

A mutation in the codon which causes a change in the coded amino acid, is known as

A. Somatic mutation

B. Recombination

C. Chromosomal inversions

*D. Missense mutation

E. Mutagenesis

You are studying functioning of a bacteria operon. The operator gene has been released from the repressor. Immediately after his the following process will start in the sell:

A. Processing

*B. Transcription

C. Translation

D. Replication

E. Repression

The two energy rich compounds utilized for protein biosynthesis are:

A. ATP and TTP

*B. ATP and GTP

C. ATP and CTP

D. GTP and UTP

E. ATP and UTP

Choose the substance that can stimulate LAC-operon expression in E.coli:

A. Mannose

*B. Lactose

C. Sucrose

D. Fructose

E. Glucose

Regarding сytosolic eukaryotic translation false is:

A. eIF2 shifts between GDP & GTP

B. Capping helps in attachment of mRNA to 40 S Ribosome

C. Releasing factor releases the polypeptide chain from the P site

D. The ribozime peptidyltransferase catalyses the formation of peptide bond

*E. N-formyl -methionyl-tRNA will be the first to come into action

Minor base in t-RNA is:

A. Methyl xanthine

B. Orotic acid

C. Cystine

D. Adenine

*E. Dihydrouracil

In the dna molecule the coding region reads 5’-cgt- 3’. This would code in the rna as:

A. 5’-UCG-3’

B. 5’-ACG-3’

C. 5’GCA-3’

*D. 5’GCU-3’

E. 5’-CGU-3’

What is the average number of high energy bonds required for the synthesis of 1 peptide bond:

*A. _4

B. _5

C. _1

D. _3

E. _2

The primary role of chaperones is to help in:

*A. Protein folding

B. Protein synthesis

C. Protein degradation

D. Protein denaturation

E. None

Leucine zipper motif is a mediator for:

A. Ligand membranes

B. Cyclic GMP

C. Cyclic AMP

*D. Binding of regulatory proteins to DNA

E. Membrane attack complexes

All amino acids are translated except one. Point out it:

A. Threonine

B. Tyrosine

C. Proline

D. Alanine

*E. Hydroxyproline

Following organelles are involved in the formation of N-glycosylated product:

A. Nucleolus

*B. Golgi apparatus

C. Smooth Endoplasmic Reticulum

D. Peroxisomes

E. Ribosomes

Choose a codon composition from following list:

A. 2 complementary base pairs

B. 4 individual nucleotides

C. 4 complementary base pairs on RNA

*D. 3 individual nucleotides

E. 2 individual nucleotides

All stated below are true about the genetic code except one. Choose it:

A. Universal

B. Non overlapping

C. Degenerate

*D. Punctuation is present

E. High specific