Biology MCQ, Class-11th, Chapter-10, Cell Cycle and Cell Division

NCERT based Biology MCQ of Class 11th, Chapter-10, Cell Cycle and Cell Division with brief explanation for competitive exams like TGT HTET, KVS PGT, SSC and all other state competition exams. 

Right Answer for MCQ will be highlighted on Hover / Click on the option.

NCERT Based MCQ with Explanation:

1. What is the primary function of the cell cycle?

A) Synthesis of proteins

B) Cell division and DNA replication

C) Protein degradation

D) Cellular respiration

Explanation: The cell cycle includes processes that lead to the division of a parent cell into two daughter cells, involving DNA replication, growth, and division.

2. During which phase does DNA synthesis occur in the cell cycle?

A) G1 phase

B) G2 phase

C) S phase

D) M phase

Explanation: DNA synthesis occurs during the S (Synthesis) phase of interphase, doubling the DNA content without changing the chromosome number.

3. Which of the following cells would most likely be in the quiescent stage (G0) of the cell cycle?

A) Heart cells

B) Skin cells

C) Liver cells

D) Bone marrow cells

Explanation: Some cells, like heart cells, stop dividing and enter the quiescent stage (G0), where they remain metabolically active but no longer proliferate.

4. What phase of the cell cycle typically follows the G1 phase?

A) G2 phase

B) S phase

C) M phase

D) Cytokinesis

Explanation: After the G1 phase, where the cell grows, the S phase begins, in which DNA replication takes place.

5. Which phase of mitosis is characterized by the alignment of chromosomes along the equator of the cell?

A) Prophase

B) Anaphase

C) Telophase

D) Metaphase

Explanation: During metaphase, chromosomes align at the cell’s equatorial plate, preparing for separation.

6. What event occurs during prophase of mitosis?

A) Chromosomes align at the equator

B) Chromosomes decondense

C) Chromosomal material condenses to form visible chromosomes

D) Cytokinesis

Explanation: Prophase marks the condensation of chromatin into visible chromosomes and the breakdown of the nuclear envelope.

7. In which phase of the cell cycle does the cell grow and prepare for DNA replication?

A) G1 phase

B) S phase

C) G2 phase

D) M phase

Explanation: The G1 phase is a period of cell growth and metabolic activity before DNA replication occurs in the S phase.

8. Which of the following describes cytokinesis in plant cells?

A) Formation of a cleavage furrow

B) Formation of a cell plate

C) Movement of chromosomes

D) Duplication of the centrosome

Explanation: In plant cells, cytokinesis occurs through the formation of a cell plate, which eventually becomes the cell wall.

9. Which enzyme is involved in crossing over during meiosis?

A) DNA polymerase

B) Ligase

C) Helicase

D) Recombinase

Explanation: Recombinase is the enzyme that facilitates the exchange of genetic material between homologous chromosomes during crossing over in meiosis.

10. Which structure serves as the attachment point for spindle fibers during mitosis?

A) Centromere

B) Kinetochore

C) Aster

D) Centrosome

Explanation: Spindle fibers attach to the kinetochore, a protein complex on the centromere of chromosomes, during mitosis.

11. What is the significance of mitosis in multicellular organisms?

A) Produces genetic diversity

B) Repairs and replaces cells

C) Reduces the chromosome number by half

D) Increases the DNA content

Explanation: Mitosis is crucial for growth, repair, and replacement of cells, maintaining the chromosome number and genetic integrity.

12. What type of cells are produced after meiosis?

A) Diploid cells

B) Haploid cells

C) Polyploid cells

D) Tetraploid cells

Explanation: Meiosis produces haploid cells, each containing half the number of chromosomes of the parent cell, essential for sexual reproduction.

13. During which phase of meiosis do homologous chromosomes separate?

A) Prophase I

B) Anaphase I

C) Metaphase II

D) Telophase II

Explanation: During anaphase I, homologous chromosomes are separated and pulled to opposite poles of the cell.

14. Which of the following processes occurs in both mitosis and meiosis?

A) Crossing over

B) Chromosome duplication

C) Reduction of chromosome number

D) Formation of tetrads

Explanation: Chromosome duplication occurs in the S phase of interphase before both mitosis and meiosis, ensuring each cell division has a complete set of chromosomes.

15. In which stage of meiosis does crossing over occur?

A) Prophase I

B) Metaphase I

C) Anaphase I

D) Telophase I

Explanation: Crossing over occurs during prophase I of meiosis, where homologous chromosomes exchange genetic material to increase genetic diversity.

16. During which stage of mitosis does the nuclear envelope reform around the daughter nuclei?

A) Prophase

B) Metaphase

C) Telophase

D) Anaphase

Explanation: In telophase, the nuclear envelope reforms around the separated daughter chromosomes, marking the end of nuclear division.

17. What is the importance of crossing over in meiosis?

A) Ensures equal chromosome number in daughter cells

B) Increases genetic variability

C) Prevents chromosome duplication

D) Ensures proper cell division

Explanation: Crossing over between homologous chromosomes during prophase I of meiosis increases genetic diversity in offspring by exchanging genetic material.

18. How many chromosomes are present in a human cell after the S phase of the cell cycle?

A) 23

B) 46

C) 69

D) 92

Explanation: The number of chromosomes remains the same at 46 (diploid number), but the amount of DNA doubles during the S phase.

19. In which phase of meiosis do sister chromatids separate?

A) Anaphase I

B) Metaphase I

C) Anaphase II

D) Telophase II

Explanation: During anaphase II of meiosis, sister chromatids separate and move towards opposite poles, similar to anaphase in mitosis.

20. Which of the following is a key event in metaphase of mitosis?

A) Chromosomes condense

B) Chromosomes align at the spindle equator

C) Chromatids separate

D) Nuclear membrane disintegrates

Explanation: In metaphase, the chromosomes are aligned at the equatorial plate of the cell, preparing for separation in anaphase.

21. Which phase is also known as the equational division?

A) Meiosis I

B) Meiosis II

C) Mitosis

D) Cytokinesis

22. What type of cell division occurs in somatic cells?

A) Mitosis

B) Meiosis

C) Binary fission

D) Fragmentation

23. What happens during the G2 phase of the cell cycle?

A) DNA replication

B) Cell growth and preparation for mitosis

C) Cytokinesis

D) Chromosome alignment

24. What type of division occurs in the cells of the germ line to produce gametes?

A) Binary fission

B) Mitosis

C) Meiosis

D) Budding

25. Which stage of meiosis results in the formation of two daughter cells that each contain half the number of chromosomes as the parent cell?

A) Telophase II

B) Anaphase I

C) Telophase I

D) Metaphase II

26. Which event is characteristic of prophase in mitosis?

A) Chromosomes align along the equator

B) Sister chromatids separate

C) Chromatin condenses into visible chromosomes

D) Spindle fibers attach to kinetochores

27. What is the final product of mitosis?

A) Two genetically identical daughter cells

B) Four genetically diverse daughter cells

C) Two haploid cells

D) Four diploid cells

28. During which phase of meiosis do homologous chromosomes pair up and form tetrads?

A) Prophase I

B) Metaphase I

C) Anaphase I

D) Telophase I

29. What is the role of spindle fibers during mitosis?

A) Break down the nuclear envelope

B) Align chromosomes along the equator

C) Replicate DNA

D) Perform cytokinesis

30. Which phase of meiosis involves the separation of homologous chromosomes?

A) Prophase I

B) Anaphase I

C) Anaphase II

D) Metaphase I

Download Complete PDF with 100+ MCQ (Each Chapter) & Explanation: