Chapter 10: Cell Cycle and Cell Division – Very Short Answer Type Questions

CBSE Class 11 Biology Very Short Answer Questions – Cell Cycle and Cell Division (Chapter 10 | NCERT)

Course & Examination Details (Systematic Format)

Course: CBSE Class 11 Biology
Unit: III – Cell Structure and Function
Chapter: 10 – Cell Cycle and Cell Division
Based on: NCERT Syllabus
Examination: CBSE Board Examination (Class XI)
Assessment Focus: Flowcharts, stage identification, comparison of divisions

Section A: Cell Cycle and Its Phases (Q1–Q15)

Q1. What is the cell cycle?
Answer:
The cell cycle is the sequence of events by which a cell grows, replicates its DNA, and divides to form daughter cells.

Q2. Name the two major phases of the cell cycle.
Answer:
The two major phases are interphase and M phase (mitotic phase).

Q3. Which phase occupies the longest duration of the cell cycle?
Answer:
Interphase occupies the longest duration of the cell cycle.

Q4. Why is interphase not considered a resting phase?
Answer:
Interphase is metabolically active, involving growth, DNA replication, and preparation for cell division.

Q5. Name the three sub-phases of interphase.
Answer:
G₁ phase, S phase, and G₂ phase are the three sub-phases of interphase.

Q6. What occurs during the G₁ phase?
Answer:
Cell growth occurs with synthesis of RNA, proteins, and duplication of organelles.

Q7. In which phase does DNA replication occur?
Answer:
DNA replication occurs during the S phase.

Q8. What happens to chromosome number during S phase?
Answer:
Chromosome number remains the same, but DNA content doubles.

Q9. What is the significance of the G₂ phase?
Answer:
G₂ phase prepares the cell for mitosis by synthesizing spindle proteins.

Q10. What is the G₀ phase?
Answer:
G₀ phase is a resting stage where cells stop dividing temporarily or permanently.

Q11. What is meant by M phase?
Answer:
M phase is the stage of cell cycle involving mitosis and cytokinesis.

Q12. Define cytokinesis.
Answer:
Cytokinesis is the division of cytoplasm resulting in two separate daughter cells.

Q13. How does cytokinesis differ in plant and animal cells?
Answer:
Animal cells form a cleavage furrow, while plant cells form a cell plate.

Q14. What ensures genetic stability during the cell cycle?
Answer:
Accurate DNA replication and equal chromosome segregation ensure genetic stability.

Q15. Why is the cell cycle essential for multicellular organisms?
Answer:
It enables growth, tissue repair, replacement of cells, and maintenance of body functions.

Section B: Mitosis (Q16–Q30)

Q16. What is mitosis?
Answer:
Mitosis is an equational division producing two genetically identical daughter cells.

Q17. In which cells does mitosis occur?
Answer:
Mitosis occurs in somatic or body cells.

Q18. Name the stages of mitosis in correct order.
Answer:
Prophase, metaphase, anaphase, and telophase.

Q19. What happens to chromatin during prophase?
Answer:
Chromatin condenses to form distinct chromosomes.

Q20. Which structures disappear during prophase?
Answer:
The nuclear membrane and nucleolus disappear during prophase.

Q21. Why is metaphase important in mitosis?
Answer:
Chromosomes align at the equatorial plane, ensuring equal separation.

Q22. What is the metaphase plate?
Answer:
It is the equatorial plane where chromosomes align during metaphase.

Q23. What key event occurs during anaphase?
Answer:
Centromeres split and sister chromatids move toward opposite poles.

Q24. What happens to chromosomes during telophase?
Answer:
Chromosomes decondense and nuclear membranes reform around them.

Q25. When does spindle apparatus disappear?
Answer:
The spindle apparatus disappears during telophase.

Q26. What is the chromosome number in daughter cells after mitosis?
Answer:
Daughter cells have the same chromosome number as the parent cell.

Q27. Why is mitosis called equational division?
Answer:
Because it maintains the same chromosome number in daughter cells.

Q28. Mention one role of mitosis in organisms.
Answer:
Mitosis helps in growth and repair of tissues.

Q29. In which stage are chromosomes most clearly visible?
Answer:
Chromosomes are most clearly visible during metaphase.

Q30. Which phase follows mitosis?
Answer:
Cytokinesis follows mitosis.

Section C: Meiosis (Q31–Q45)

Q31. What is meiosis?
Answer:
Meiosis is a reduction division producing four haploid daughter cells.

Q32. In which cells does meiosis occur?
Answer:
Meiosis occurs in germ cells producing gametes.

Q33. How many divisions occur in meiosis?
Answer:
Two successive divisions occur in meiosis.

Q34. Name the two stages of meiosis.
Answer:
Meiosis I and Meiosis II.

Q35. Which stage of meiosis is reductional?
Answer:
Meiosis I is the reductional division.

Q36. In which stage does synapsis occur?
Answer:
Synapsis occurs during the zygotene stage of prophase I.

Q37. What is crossing over?
Answer:
Crossing over is the exchange of genetic material between homologous chromosomes.

Q38. During which stage does crossing over occur?
Answer:
Crossing over occurs during the pachytene stage of prophase I.

Q39. What are chiasmata?
Answer:
Chiasmata are points where crossing over between chromatids occurs.

Q40. What separates during anaphase I of meiosis?
Answer:
Homologous chromosomes separate during anaphase I.

Q41. What separates during anaphase II?
Answer:
Sister chromatids separate during anaphase II.

Q42. How many daughter cells are formed at the end of meiosis?
Answer:
Four haploid daughter cells are formed.

Q43. Why is meiosis important in sexual reproduction?
Answer:
It produces haploid gametes and maintains chromosome number across generations.

Q44. How does meiosis contribute to variation?
Answer:
Through crossing over and independent assortment of chromosomes.

Q45. Meiosis II resembles which type of division?
Answer:
Meiosis II resembles mitosis.

Section D: Significance of Cell Division (Q46–Q50)

Q46. Why is cell division essential for growth?
Answer:
It increases cell number, enabling growth and development.

Q47. How does cell division help in repair?
Answer:
It replaces damaged or dead cells with new cells.

Q48. What is the evolutionary significance of meiosis?
Answer:
It generates genetic variation, promoting evolution.

Q49. Which type of division maintains chromosome number?
Answer:
Mitosis maintains chromosome number.

Q50. Which type of division reduces chromosome number?
Answer:
Meiosis reduces chromosome number to half.

✅ Academic Relevance

✔ Strictly aligned with NCERT Class 11 Biology
✔ Ideal for CBSE very short answer questions
✔ Strong focus on definitions, stages, and comparisons