Multiple Choice Questions on Molecular Genetics

1. The end product of translation are

a) amino acids

b) lipids

c) polypeptides

d) all of these

2. All viruses consists of

a) DNA and protein coat

b) RNA and protein coat

c) Polysaccharides and proteins

d)a nucleic acid and a protein coat

3. In bacteria, a small circle of DNA found outside the main chromosome is called a

a) plasmid

b)protein

c)genetic fingerprint

d)episome

4. The genetic instructions for forming a polypeptide chain are carried to the ribosome by the

a)tRNA

b)rRNA

c)mRNA

d)DNA

5. The DNA of an elephant and the DNA of a mango tree will probably differ in all of the following

a) Sequence of DNA nucleotides

b) Length of DNA molecules

c) Number of DNA molecules

d) Kinds of nucleotides utilized in forming DNA

6. The lac operon in E.coli is involved in

a) Regulating the expression of a gene

b) Controlling DNA replication

c) Regulating the translation of mRNA

d) Controlling the formation of ribosomes

7. Genetic variation can be introduced into bacteria by all of the following methods except:

a)transduction

b)mutation

c)transformation

d)DNA amplification

8. Which of the following would most likely cause a mutation with the greatest deleterious effect?

a) An insertion of a nucleotide triplet into a DNA strand that codes for an mRNA

b)  A single addition of a nucleotide in a DNA strand that codes for an mRNA

c) a deletion of a nucleotide triplet from a DNA strand that codes for an mRNA

d) all of these

9. All of the following enzymes are involved in DNA replication except:

a) helicase

b) primase

c) DNA polymerase

d) RNA polymerase

10. Which of the following is true?

a) A messenger RNA molecule has the form of a double helix

b) Ribosomes contain RNA nucleotides and amino acids

c) The uracil nucleotide consists of the uracil nitrogen base, a deoxyribose sugar and a phosphate group.

d) In eukaryotes, DNA is manufactured in the nucleus and RNA is manufactured in the cytoplasm.

Answers
1c) polypeptides
2d)a nucleic acid and a protein coat
3a)plasmid
4c)mRNA
5d)Kinds of nucleotides utilized in forming DNA
6a)Regulating the expression of a gene
7d)DNA amplification
8b)A single addition of a nucleotide in a DNA strand that codes for an mRNA
9d)RNA polymerase
10b)Ribosomes contain RNA nucleotides and amino acids