Molecular Basis of Inheritance — Page 11 | NEET Biology

Q101

A complex of ribosomes attached to a single strand of RNA is known as

A Polysome

B Polymer

C Polypeptide

D Okazaki fragment

Correct Answer

Option A

Solution

(a) Polysome (polyribosome) = multiple ribosomes on one mRNA for simultaneous translation.

Q102

Which of the following RNAs should be most abundant in animal cell?

A tRNA

B mRNA

C miRNA

D rRNA

Correct Answer

Option D

Solution

(d) rRNA is most abundant (~80% of total cellular RNA).

Q103

Select the correct match

A Alec Jeffreys - Streptococcus pneumoniae

B Alfred Hershey and Martha Chase - TMV

C Francois Jacob and Jacques Monod - Lac operon

D Matthew Meselson and F. Stahl - Pisum sativum

Correct Answer

Option C

Solution

(c) Francois Jacob and Jacque Monod proposed the model of gene regulation known as operon model/lac operon.

Alec Jeffreys gave DNA fingerprinting technique.

Matthew Meselson and F.

Stahl gave semi-conservative DNA replication in E.coli.

Alfred Hershey and Martha Chase proved DNA as genetic material not protein.

Q104

AGGTATCGCAT is a sequence from the coding strand of a gene. What will be the corresponding sequence of the transcribed mRNA?

A AGGUAUCGCAU

B UGGTUTCGCAT

C UCCAUAGCGUA

D ACCUAUGCGAU

Correct Answer

Option A

Solution

(a) Coding strand and mRNA have the similar nucleotide sequence except, Thymine (T) is replaced by Uracil (U) in mRNA.

Q105

What will be the sequence of mRNA produced by the following stretch of DNA? Template strand: 3 ATGCATGCATGCATG 5

A 3 AUGCAUGCAUGCAUG 5

B 5 AUGCAUGCAUGCAUG 3

C 5 UACGUACGUACGUAC 3

D 3 UACGUACGUACGUAC 5

Correct Answer

Option C

Solution

(c) The coding strand 5 TACGTACGTACGTAC 3 gives mRNA 3 UACGUACGUACGUAC 5.

In mRNA, at the place of thymine in coding strand uracil is present.

Q106

Match the following RNA polymerases with their transcribed products

A RNA pol I - rRNA

B RNA pol II - hnRNA

C RNA pol III - tRNA

D All of the above

Correct Answer

Option D

Solution

(d) RNA polymerase is an enzyme that is responsible for copying a DNA sequence into an RNA sequence during the process of transcription.

In eukaryotes, there are three types of RNA polymerases.

RNA polymerase I transcribes rRNAs genes.

RNA polymerase II transcribes hnRNAs.

RNA polymerase III transcribes tRNAs and 5S rRNA.

Q107

In the process of transcription in Eukaryotes, the RNA polymerase I transcribes

A Precursor of mRNA, hnRNA

B mRNA with additional processing, capping and tailing

C tRNA, 5 srRNA and snRNAs

D rRNAs - 28S, 18S and 5.8S

Correct Answer

Option D

Solution

(d) During transcription in eukaryotes, RNA polymerase I transcribes $5.8S, 18S$ and $28S$ rRNA.

Q108

From the following, identify the correct combination of salient features of Genetic Code.

A Degenerate,Non-overlapping,Nonambiguous

B Universal, Non-ambiguous, Overlapping

C Degenerate, Overlapping, Commaless

D Universal, Ambiguous, Degenerate

Correct Answer

Option A

Solution

(a) Genetic code is the sequence of nucleotides in deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) that determines the amino acid sequence of proteins.

Genetic code is universal, unambiguous, non overlapping and degenerate in nature.

Q109

The first phase of translation is initiation

A Recognition of the DNA molecule

B Aminoacylation of tRNA

C Recognition of an anti-codon

D Binding of mRNA to ribosome

Correct Answer

Option B

Solution

(b) The first phase of translation involves activation of amino acid in the presence of ATP and linked to their cognate tRNA - a process commonly called as charging of tRNA or aminoacylation of tRNA.

Q110

Genetic code consists of nucleotides

A adenine and guanine

B cytosine and uracil

C cytosine and guanine

D all the above.

Correct Answer

Option D

Solution

(d) Genetic code is the relationship between the amino acid sequence in a polypeptide chain and the base sequence of mRNA.

It includes adenine, guanine, cytosine and uracil.