Cell Cycle and Cell Division — Page 2 | NEET Biology

Q11

In the somatic cell cycle, DNA replication occurs during the S phase.

A In G1 phase DNA content is the same as the amount of DNA present in the original cell

B DNA replication takes place in S-phase

C A long interphase is followed by a short mitotic phase

D G2 phase follows mitotic phase

Correct Answer

Option B

Solution

(b) DNA replication is restricted to S-phase of interphase.

Q12

At what stage of the cell cycle are histone proteins synthesized in a eukaryotic cell?

A During G2 stage of prophase

B During S-phase

C During entire prophase

D During telophase

Correct Answer

Option B

Solution

(b) Histone proteins are synthesized during S-phase of cell cycle.

Q13

Some dividing cells exit the cell cycle and enter vegetative inactive stage G0. This process occurs at the end of

A G1 phase

B S phase

C G2 phase

D M phase

Correct Answer

Option D

Solution

(d) The quiescent stage G0 occurs at the end of M-phase and beginning of G1 phase.

Q14

Meiosis I is reductional division. Meiosis II is equational division due to

A pairing of homologous chromosomes

B crossing over

C separation of chromatids

D disjunction of homologous chromosomes

Correct Answer

Option C

Solution

(c) Meiosis II is equational for maintaining the haploid number by separating the two chromatids of a chromosome.

Q15

In meiosis, the daughter cells differ from parent cell as well as amongst themselves due to

A segregation, independent assortment and crossing over

B segregation and crossing over

C independent assortment and crossing over

D segregation and independent assortment

Correct Answer

Option A

Solution

(a) Due to segregation, independent assortment and crossing over, daughter cells exhibit variation.

Q16

Meiosis II performs

A separation of sex chromosomes

B synthesis of DNA and centromere

C separation of homologous chromosomes

D separation of chromatids

Correct Answer

Option D

Solution

(d) Meiosis II is equational division for maintaining the haploid number, separating the chromatids from each other.

Q17

Meiosis is evolutionary significant because it results in

A genetically similar daughters

B four daughter cells

C eggs and sperms

D recombinations

Correct Answer

Option D

Solution

(d) Meiosis provides a chance for new combinations of chromosomes through crossing over and random distribution.

Q18

Lampbrush chromosomes occur during

A prophase of mitosis

B diplotene of meiosis

C metaphase of meiosis

D interphase

Correct Answer

Option B

Solution

(b) Lampbrush chromosomes are highly elongated bivalent chromosomes of diplotene stage.

Q19

The exchange of genetic material between chromatids of paired homologous chromosomes during first meiotic division is called

A transformation

B chiasmata

C crossing over

D synapsis

Correct Answer

Option C

Solution

(c) Crossing over is the exchange of genetic material between chromatids of paired homologous chromosomes.

Q20

Genetic map is one that

A shows the distribution of various species in a region

B establishes sites of the genes on a chromosome

C establishes the various stages in gene evolution

D show the stages during the cell division

Correct Answer

Option B

Solution

(b) Genetic mapping establishes sites of the genes on a chromosome.