Molecular Basis of Inheritance Set 2 MCQs

Q1 | Which one is a ribozyme ?

Helicase

Ribonuclease - P

Peptidyl transferase

Both (B) & (C)

Q2 | Which of the following pairs is not correctly matched ?

Recombinant DNA - DNA forming by union of segments of DNA from diffrent Sources

Purines - Nitrogenous bases Cytosine , thymine and Uracil

ATP - The principal energy carrying compound inthe cell

r-RNA - RNA molecules found in ribosomes

Q3 | Which one of the following pairs is correctly matched ?

Ribosomal RNA - Carries amino acids to the site of protein synthesis

Transcription - Process by which protein in synthesized

Translation - Process by which m RNA carries the information from nucleus to ribosomes

Anticodon - Site of t-RNA that binds to the m-RNA

Q4 | Which is not the step of translation ?

Initiation

Replication

Elongation

Termination

Q5 | The enzyme amino acyl t-RNA-synthetase facilitates.

Joining two neighbouring amino acids on ribosomes

A doption of amino acids by a t-RNA molecule

Insertion of amino acyl t-RNA into the ribosome sites

Transfer of amino acyl t-RNA from the ribosomal ‘A’ site to ‘P’ site

Q6 | state the anticodon of initiation codon of protein synthesis

UAC

UUU

CAU

AUG

Q7 | Which is the energy source for the process of elongation ?

ATP

GTP

Creatine-PO4

All the above

Q8 | What does a gene consist of ?

Promoter

Initiation site & termination site

coding sequence

All the above

Q9 | Name the enzymes needed for lactose Catabolism in E.coli ?

? - galactosidase, permease transacetylase

? - galactosidasee Lactase, transacetylase

? - galactosidase, lactase, permease

Lactase, permease, transacetylase

Q10 | What does operon contain ?

Regulator gene + promotor gene

Operator gene + structural gene

Regulator gene + promotor gene structural gene

Regulator gene + promotor gene + operator gene + structural gene

Q11 | Select correct match with respect to lac-operon model ?

Active represser + inducer ? Inactive repressor

Active repressor + corepressor ? Inactive repressor

Inactive repressor + inducer ? Active repressor

Inactive repressor + corepressor? Active repressor

Q12 | In relation of lac operon in E-coli , Which protein is not regulated by the repressor ?

Tryptophan

galactosidase

Lactose permease

Transacetylase

Q13 | Which is not correct regarding the activity of helicase during DNA replication ?

Cuts hydrogen bomds

Requires ATP

separates DNA strands

Stabilizes single strands

Q14 | Which of the following enzyme is not produced by E. coli during lactose catabolism ?

? - galactosidase

Thioglactoside translacetylase

Lactose dehydrogenase

Lactose permease

Q15 | Which is the incorrect statement regarding HGP ?

HGP is an Indian scientific research project

In 1990, the Project was initiated

A working draft of the genome was announced in 2000

In February 2001, the analysis of the working draft was published

Q16 | Humans have approximately _____ times more genes than E.coli

8

15

100

50

Q17 | Which of the following is not according to the chargoff’s rule ?

A = T

C = G

A + G = T + C

A + T / G + C =1

Q18 | Select the correct answer / answers from the following1. Ligase :- Joins short segments of DNA together2. DNA Polymerase :- cuts DNA at specific sequence3. Helicase :- Breaks the hydrogen bonds between complementary pairs during DNA replication4. Gyrase : - Joins weak hydrogen bonds between complementary pairs

1, 2, 3 and 4, are corrent

1 and 2 are correct, 3 and 4 are false

1 and 3 are correct, 2 and 4 false

1, 2, 3 are correct, 4 is false

Q19 | DNA replication in eukaryotes is

Unidirectional with many origin

Bidirectional with many origin

Unidirectional with single origin

Bidirectional with single origin

Q20 | Aminoacids lysine, serine and arginine are coded by how many codons ?

6, 4, and 3 respectively

4, 2 and 2 respectively

6 codons

4 codons

Q21 | Which of the following amino acid is coded by 3 codons ?

serine

Proline

Tryptophan

Isoleucine

Q22 | How many nucleotides make one okazaki segment in eukaryotes ?

1000-1500

100-200

5000

Not fixed

Q23 | Which of the following enzymes help in the process of formation of phosphodiester bond during reverse transcription ?

DNA - dependant RNA polymerase

DNA dependant DNA polymerase

RNA - dependant RNA polymerase

RNA - dependant DNA polymerase

Q24 | The two strands of a DNA molecule are separted and one of them is analysed for its A + T / G + C ratio, This is found to be 0.2 What is the A + T / G + C ratio of the other strand

0.02

0.08

0.8

0.2

Q25 | DNA replication in lagging strand of most of the eukaryotic organis ms is

conservative and continuous

semi conservative but discontinuous

conservative and semi - discontinuous

semi conservative but continuous