Cell Cycle and Cell Division Questions and Answers

1. Which of the following options gives the correct sequence of events during mitosis?
A. Condensation – nuclear membrane – disassembly crossing over segregation – telophase
B. Condensation – nuclear membrane disassembly – arrangement at equator centromere division – segregation telophase
C. condensation – crossing over nuclear – membrane disassembly – segregation telophase
D. condensation – arrangement at equator centromere division – segregation telophase

2. Anaphase Promoting Complex (APC) is a protein degradation machinery necessary for proper mitosis of animal cells. If APC is defective in a human cell, which of the following is expected to occur?
A. Chromosomes will not condense
B. Chromosomes will be fragmented
C. Chromosomes will not segregate
D. Recombination of Chromosomes arm will occur

3. During cell growth, DNA synthesis takes place in-
A. G1 Phase
B. S-Phase
C. M Phase
D. G2-Phase

4. When cell has stalled DNA replication fork, which checkpoint should be predominantly ctivated?
A. G2/M
B. G1/S
C. Both G2/M and M
D. M

5. In meiosis crossing over is initiated at
A. Zygotene
B. Diplotene
C. Pachytene
D. Leptotene

6. Which of the following is not a characteristic feature during mitosis in somatic cells?
A. Chromosome movement
B. Synapsis
C. Spindle fibres
D. Disappearance of nucleolu

7. Which of these is not a key feature of meiosis?
A. Meiosis involves two sequential cycles of nuclear and cell division
B. Meiosis involves pairing of homologous chromosomes
C. Two cycles of DNA replication occur during meiosis
D. There is recombination between the paired homologous chromosomes

8. Which of the following phases correspond to the interval between mitosis and initiation of DNA replication?
A. S phase
B. G phase
C. G2 phase
D. M phase

9. The checkpoint in cell cycle plays important role in-
A. repair DNA damage
B. apoptosis initiation
C. assess DNA damage
D. inhibit cell damage

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

A. (i), (ii), (iii), (iv)
B. (ii), (iii), (iv), (i)
C. (ii), (i), (iv), (iii)
D. (ii), (i), (iii), (iv)

11. Which one of the following is wrong for meiosis?
A. It leads to formation of sister chromatids
B. It occurs in diploid cell
C. It occurs in haploid cell
D. It occurs by splitting of centromeres and separation of sister chromatids

12. Which of the following does not occur in the interphase of eukaryotic cell division?
A. Increase of ATP synthesis
B. Increase of DNA synthesis
C. Increase of RNA synthesis
D. d Reduction in cell size

13. Which one of the following is the significance of mitosis?
A. Restricted to haploid cells
B. Cell repair
C. Increases the genetic variability
D. Recombination of chromosomes

14. Find out the correct statement-
A. During mitosis endoplasmic reticulum and nucleolus disappear completely at early prophase
B. Chromosomes are arranged along the equator during prophase of mitosis
C. Chromosome is made up of two sister chromatids at anaphase of mitosis
D. Small disc shaped structures at the surface of the centromeres that appear during metaphase are kinetochores

15. In a typical eukaryotic cell cycle, Gap 1, Synthesis and Gap 2 are the three phases included in the-
A. Prophase
B. metaphase
C. anaphase
D. interphase

16. An example of mitogen is
A. cytokinin
B. glucose
C. glycerol
D. fructose

17. Crossing over occurs in the ________ stage of meiosis.
A. zygotene
B. leptotene
C. pachytene
D. diplotene

18. The stage between two meiotic divisions is called as ________
A. Diakinesis
B. Interkinesis
C. diplotene
D. interphase

19. Chromosomes start pairing in which stage of meiosis?
A. Leptotene
B. Zygotene
C. Pachytene
D. Diplotene

20. During meiosis I, the number of chromosomes is-
A. Halved
B. Tripled
C. Doubled
D. Quadrupled

21. Some cells in adult animals do not divide. They exit G, phase and enter an inactive stage which is called as
A. G2 phase
B. G0 phase
C. S phase
D. M phase

22. Identify the correct combination regarding anaphase, anaphase I and anaphase II
A. Anaphase – centromere splits, Anaphase I – centromere splits, Anaphase II – centromere splits
B. Anaphase – chromatids move to opposite poles, Anaphase I – homologous chromosomes separate, Anaphase II – centromere splits
C. Anaphase – chromosomes cluster at opposite poles, Anaphase I – homologous chromosomes separate, Anaphase II – centromere splits
D. Anaphase – chromosomes move to one pole, Anaphase I – homologous chromosomes separate, Anaphase II –centromere splits.

23. Assertion (A) (A): Events in pachytene play a key role in evolutionary changes in organisms
Reason (R): Exchange of genetic material takes place between sister chromatids or homologous chromosomes
A. A and R are true, R is correct explanation of A
B. Both A and R are true, R is not the correct explanation of A
C. A is true, R is false
D. A is false, R is true.

24. Which is the longest phase of the cell cycle?
A. M-phase
B. Leptotene
C. Interphase
D. S-phase

25. During which phase(s) of cell cycle, amount or DNA In a cell remains at 4C level if the initial amount is denoted as 2C?
A. G1 and S
B. G2 and M
C. G0 and G1
D. Only G2

26. In’S phase of the cell cycle
A. amount of DNA doubles in each cell
B. amount of DNA remains same in each cell
C. chromosome number is increased
D. amount of DNA is reduced to halt in each cell

27. The enzyme recombinase is required at which stage of meiosis?
A. Pachytene
B. Diplotene
C. Zygotene
D. Diakinesis

28. Select the correct statement related to mitosis –
A. Amount of DNA in the parent cell is first doubled and then distributed into four daughter cells
B. Amount of DNA in the parent cell is first halved and then distributed into four daughter cells
C. Amount of DNA in the parent cell is first doubled and then distributed into two daughter cells
D. Amount of DNA in the parent cell is first halved and then distributed into two daughter cells

29. Statement A For a particular character in an individual, each gamete gets only one allele.
Statement B: Chromatids of a chromosome split (separate) and move towards opposite poles during anaphase of mitosis.
A. statement A is correct and statement B is wrong
B. Both the statements are correct and B is the reason for A
C. Statement B is correct and statement A is wrong
D. Both the statements are correct and B is not the reason for A.

30. The centrosome duplicates during the-
A. G2 phase of cell cycle
B. S-phase of cell cycle
C. Prophase of cell cycle
D. G1 phase of cell cycle

31. Cell cycle includes the sequence
A. S, G1, G2, M
B. S, M, G1, G2
C. G1, S, G2, M
D. M, G1, G2, S

32. What are spindle fibres that connect the centromere to respective poles called-
A. Astral rays
B. Interphase fibres
C. Chromosomal fibres
D. Interchromosomal fibres

33. The complex formed by a pair of synapsed homologous chromosomes is called
A. Bivalent
B. equatorial plate
C. Kinetocnore
D. axoneme

34. Assertion: Meiosis ll is Similar to mitosis.
Reason : Meiosis I cannot occur in haploid cells.
A. If both are true with reason being correct explanation
B. Both true but reason is not correct explanation
C. Assertion true but reason is wrong
D. both are wrong

35. Which of the following events takes place during anaphase stage of mitosis
I. Spindle fibre attach to Kinetochores of chromosomes
II. Centromeres split and chromatids separate
III. Chromatids move to opposite poles
IV. Nucleolous, Golgi complex and E.R. reform
A. I and II only
B. III and IV only
C. II and III only
D. L and IV only

36. During meiosis I, the chromosomes start pairing at
A. Zygotene
B. Diplotene
C. Pachytene
D. leptotene

37. During the metaphase stage of mitosis, spindle fibres attach to chromosomes at
A. Kinetochore
B. both centromere and kinetochore
C. centromere, kinetochore and areas adjoining centromere
D. centromere

38. A bivalent of meiosis I consists of
A. four chromatids and two centromeres
B. two chromatids and one centromere
C. two chromatids and two centromeres
D. four chromatids and four centromeres.

39. The homologous genes are separated at
A. Anaphase
B. Diplotene
C. Pachytene
D. Anaphase II

40. Metaphase chromosome appears to be longitudinally divided into two identical parts known as
A. sister chromosomes
B. satellites
C. daughter chromosomes
D. sister chromatids

41. Microtubule depolymerising drug such as colchicine is expected to
A. include formation of multiple contractile rings
B. allow mitosis beyond metaphase
C. inhibit cytokinesis
D. inhibit spindle formation during mitosis

42. Which of the following statement is incorrect about G0 Phase?
A. Mitosis occurs after G0 phase
B. Biocatalysts can be used to exit G0 phase
C. Cell volume keeps on increasing during this phase
D. Cell metabolism occurs continuously in G0 phase

43. Identify the meiotic stage in which the homologous chromosomes separate while the sister chromatids remain associated at their centromeres
A. Metaphase I
B. Anaphase
C. Metaphase I
D. Anaphase

44. During gamete formation, the enzyme recombinase participates during-
A. metaphase-I
B. prophase- II
C. anaphase-II
D. prophase-I

45. Find the correctly matched pairs and choose the correct option
A. Leptotene – The chromosomes become invisible
B. Zygotene-Pairing of homogenous chromosomes
C. Pachytene-Dissolution of the synaptonemal complex takes place
D. Diplotene-Bivalent chromosomes appear as tetrads
E. Diakinesis – Terminalisation of chiasmata take place
A. A and B are correct
B. B and D are correct
C. B and E are correct
D. B and Care correct

46. Which of the following events are not characteristic features of telophase?
A. Chromosome material condenses to form compact mitotic chromosomes
B. Nucleolus, Golgi complex and ER reform
C. Nuclear envelope assembles around the chromosome clusters
D. Centromeres split and chromatids separate
E. Chromosomes cluster at opposite, spindle poles and their identity as discrete elements is lost
A. A, B and D only
B. B and C only
C. A and D only
D. C, D and E only

47. Visible expression of the genetic phenomenon of crossing over is called-
A. Recombination
B. Condensation
C. Chiasmata
D. spiralisation

48. The chromosomes become gradually visible with compaction of chromatin during the meiotic stage
A. diplotene
B. leptotene
C. zygotene
D. pachytene

49. Yeast cell can progress through the cell cycle in about-
A. 30 minutes
B. 90 minutes
C. 60 minutes
D. 120 minutes

50. In onion root tip during metaphase stage of mitosis the number of kinetochores will be
A. 4
B. 8
C. 32
D. 16