Cell Cycle and Cell Division

Anaphase Promoting Complex (APC) is a protein degradation machinery necessary for proper mitosis of animal cell. If APC is defective in a human cell, which of the following is expected to occur?

1. Chromosomes will be fragmented.
2. Chromosomes will not segregate.
3. Recombination of chromosome arms will occur.
4. Chromosomes will not condense.

Spindle fibres attach on to

1. centromere of the chromosome
2. kinetosome of the chromosome
3. telomere of the chromosome
4. kinetochore of the chromosome.

Which of the following is not a characteristic feature during mitosis in somatic cells?

1. Chromosome movement
2. Synapsis
3. Spindle fibres
4. Disappearance of nucleolus

In meiosis crossing over is initiated at

1. zygotene
2. diplotene
3. pachytene
4. leptotene.

During cell growth, DNA synthesis takes place on

1. S-phase
2. G1-phase
3. G2-phase
4. M phase

When cell has stalled DNA replication fork, which checkpoint should be predominantly activated?

1. G1/S
2. G2/M
3. M
4. Both G2/M and M

Match the stages of meiosis in column I to their characteristic features in column II and select the correct option using the codes given below.

1. (a)-(iii), (b)-(iv), (c)-(ii), (d)-(i)
2. (a)-(i), (b)-(iv), (c)-(ii), (d)-(iii)
3. (a)-(ii), (b)-(iv), (c)-(iii), (d)-(i)
4. (a)-(iv), (b)-(iii), (c)-(ii), (d)-(i)

Arrange the following events of meiosis in correct sequence (i) Crossing over (ii) Synapsis (iii) Terminalisation of chiasmata (iv) Disappearance of nucleolus

1. (i), (ii), (iii), (iv)
2. (ii), (iii), (iv), (i)
3. (ii), (i), (iv), (iii)
4. (ii), (i), (iii), (iv)

A somatic cell that has just completed the S phase of its cell cycle, as compared to gamete of the same species, has

1. twice the number of chromosomes and four times the amount of DNA
2. four times the number of chromosomes and twice the amount of DNA
3. twice the number of chromosomes and twice the amount of DNA
4. same number of chromosomes but twice the amount of DNA.

Select the correct option.

1. (A) - (i); (B) - (ii); (C) - (v); (D) - (iv)
2. (A) - (ii); (B) - (iii); (C) - (iv); (D) - (v)
3. (A) - (ii); (B) - (i); (C) - (iii); (D) - (iv)
4. (A) - (ii); (B) - (iii); (C) - (v); (D) - (iv)