Molecular Basis of Inheritance — Page 2 | NEET Biology

Q11

DNA replication is

A conservative and discontinuous

B semiconservative and semidiscontinuous

C semiconservative and discontinuous

D conservative

Correct Answer

Option C

Solution

(c) DNA replication is semi-conservative (proven by Meselson-Stahl) and semi-discontinuous.

Q12

Initiation codon of protein synthesis (in eukaryotes) is

A GUA

B GCA

C CCA

D AUG

Correct Answer

Option D

Solution

(d) AUG is the universal start codon coding for methionine in eukaryotes.

Q13

Anticodon is an unpaired triplet of bases in an exposed position of

A mRNA

B rRNA

C tRNA

D sRNA

Correct Answer

Option C

Solution

(c) tRNA has the anticodon loop which pairs with the complementary codon on mRNA.

Q14

One function of the telomeres in a chromosome is to

A identify the correct number of the homologous pair of chromosomes

B help two chromatids to move towards poles

C seal the ends of chromosomes

D start RNA synthesis

Correct Answer

Option C

Solution

(c) Telomeres seal and protect chromosome ends from degradation and fusion.

Q15

Types of RNA polymerase required in nucleus for RNA synthesis in eukaryotes?

A 1

B 2

C 3

D 4

Correct Answer

Option C

Solution

(c) Eukaryotes have 3 nuclear RNA polymerases: I (rRNA), II (mRNA), III (tRNA, 5S rRNA).

Q16

Out of 64 codons, 61 codons code for 20 types of amino acid. It is called

A degeneracy of genetic code

B overlapping of gene

C wobbling of codon

D universality of codons

Correct Answer

Option A

Solution

(a) Degeneracy of genetic code means multiple codons code for the same amino acid.

Q17

Degeneration of a genetic code is attributed to the

A third member of a codon

B first member

C second member

D all three members

Correct Answer

Option A

Solution

(a) Wobble hypothesis: third base of codon is responsible for degeneracy.

Q18

Infectious proteins are present in:

A Gemini viruses

B Prions

C Viroids

D Satellite viruses

Correct Answer

Option B

Solution

(b) Infections proteins are rich in prions.

Prions are made of proteins without nucleic acid.

It is the causal agent of scrapie disease of sheep.

Q19

The unequivocal proof of DNA as the genetic material came from the studies on a

A bacterium

B fungus

C viroid

D bacterial virus

Correct Answer

Option D

Solution

(d) Bacteriophage was used by Hershey and Chase to prove DNA as genetic material.

Q20

If one strand of DNA has the nitrogenous base sequence at ATCTG, what would be the complementary RNA strand sequence

A TTAGU

B UAGAC

C AACTG

D ATCGU

Correct Answer

Option B

Solution

(b) Sequence of DNA is ATCTG then sequence of m-RNA will UAGAC.

As adenine base pairs with uracil and guanine with cytosine.