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NEET MCQs On Cell Cycle and Cell Division

DEEKSHA August 27, 2025

Cell Cycle and Cell Division – NEET Notes with MCQs & Concept Explanations

Cell Cycle and Cell Division

One of the most fundamental functions of life is cell division. Every living thing starts as a single cell and uses the remarkable process of the cell cycle to grow, develop, and reproduce. The preparation, duplication, and division of cells to create new cells are covered in this chapter.
Because questions about mitosis, meiosis, and cell cycle phases are commonly asked, this chapter is crucial for NEET. Let's go gradually, using MCQs to facilitate revision and topic reminders.

An Overview of the Cell Cycle

The cell cycle is the series of events that a cell goes through as it divides and grows.
 It is divided into two main stages:
 1. Interphase: the initial phase of preparation (cell growth and DNA replication).
 2. The M phase (mitotic phase) is when the cytoplasm (cytokinesis) and nucleus (karyokinesis) actually divide.

Interphase: The Stage of Preparation

Interphase is a very active stage during which the cell gets ready to divide; it is not a resting phase.
There are three steps to it:
G1 phase (Gap 1): Proteins and organelles are produced, and the cell expands.
Chromosomes duplicate and DNA replication takes place during the S phase (synthesis).
Cells check for faults and get ready for mitosis during the G2 phase (Gap 2).
Interphase takes up about 95% of the total cell cycle time.

Equational Division in Mitosis

Because the number of chromosomes in the daughter cells stays the same as in the parent cell, mitosis, which takes place in somatic cells, is known as equational division.
 The stages of mitosis:
 1. Prophase: nuclear membrane begins to thin, spindle fibers emerge, and chromosomes condense.
 2. Metaphase: At the equator, chromosomes align.
 3. Sister chromatids split apart and travel to opposing poles during anaphase.
 4. Telophase: Chromosomes uncoil and the nuclear membrane recovers.
Finally, cytokinesis divides the cytoplasm, forming two identical daughter cells.
Mitosis ensures growth and repair in organisms.

Meiosis: Division of Reduction

Meiosis, which is known as reduction division because the number of chromosomes is halved (diploid → haploid), takes place in germ cells to produce gametes.
 Two successive divisions:
 1. The reductional division, or meiosis I, occurs when homologous chromosomes split apart and the number of chromosomes is cut in half.
 2. Meiosis II (Equational division): Sister chromatids split apart, just like in mitosis..
Meiosis introduces genetic variation through crossing over (in Prophase I) and independent assortment.
NEET MCQs On Cell Cycle and Cell Division

NEET MCQs with Concept Explanations


Q1. The stage of cell cycle where DNA replication takes place is:
A) G1 phase
B) S phase 
C) G2 phase
D) M phase
Answer : B) S phase
Concept explanation: DNA replication always occurs in the S phase of interphase.

Q2. Which phase occupies the maximum duration in a cell cycle?
A) Prophase
B) S phase
C) Interphase 
D) M phase
Answer : C) Interphase
Concept explanation: Interphase (~95%) is the longest phase of the cell cycle.

Q3. Mitosis is also known as:
A) Reduction division
B) Equational division 
C) Resting division
D) Amitosis
Answer : B) Equational division
Concept explanation: Daughter cells have the same chromosome number as parent cells in mitosis.

Q4. Crossing over takes place during:
A) Prophase of mitosis
B) Prophase I of meiosis 
C) Anaphase I of meiosis
D) Telophase of mitosis
Answer : B) Prophase I of meiosis
Concept explanation: Crossing over (exchange of genetic material) occurs in pachytene stage of Prophase I of meiosis.

Q5. Which of the following occurs in both mitosis and meiosis?
A) Crossing over
B) Pairing of homologous chromosomes
C) Separation of sister chromatids 
D) Reduction of chromosome number
Answer : C) Separation of sister chromatids
Concept explanation: In anaphase of mitosis and anaphase II of meiosis, sister chromatids separate.

Q6. The diploid chromosome number in humans is 46. How many chromosomes will be present in each daughter cell after meiosis?
A) 92
B) 46
C) 23 
D) 69
Answer : C) 23
Concept explanation: Meiosis reduces the chromosome number to half, so gametes have 23 chromosomes.

Q7. The phase between two successive cell divisions is called:
A) Cytokinesis
B) Interphase 
C) Karyokinesis
D) Telophase
Answer : B) Interphase
Concept explanation: Interphase is the "in-between" stage where the cell prepares for the next division.

Q8. Which event is unique to meiosis and not found in mitosis?
A) Spindle formation
B) Cytokinesis
C) Synapsis and crossing over 
D) Chromosome condensation
Answer : C) Synapsis and crossing over 
Concept explanation: Synapsis (pairing of homologous chromosomes) and crossing over are hallmarks of meiosis I.

Q9. Which checkpoint ensures that the cell is ready for DNA replication?
A) G1 checkpoint 
B) G2 checkpoint
C) M checkpoint
D) Cytokinesis checkpoint
Answer : A) G1 checkpoint
Concept explanation: At the G1 checkpoint, the cell decides whether to enter S phase or not.

Q10. Synaptonemal complex is formed during:
A) Leptotene
B) Zygotene 
C) Pachytene
D) Diplotene
Answer : B) Zygotene
Concept explanation: Synapsis (pairing of homologous chromosomes) occurs in zygotene stage of Prophase I.

Q11. Which phase of meiosis is longest?
A) Metaphase I
B) Prophase I 
C) Anaphase I
D) Telophase II
Answer : B) Prophase I 
Concept explanation: Prophase I is very long because it has 5 substages (Leptotene → Zygotene → Pachytene → Diplotene → Diakinesis).

Q12. Colchicine arrests cell division at:
A) Prophase
B) Metaphase 
C) Anaphase
D) Telophase
Answer : B) Metaphase
Concept explanation: Colchicine prevents spindle formation → chromosomes can’t separate → cell stuck in metaphase.

Q13. Which of the following is a feature of meiosis but not mitosis?
A) DNA replication
B) Chromosome condensation
C) Chiasmata formation 
D) Cytokinesis
Answer : C) Chiasmata formation
Concept explanation: Chiasmata (cross-shaped structure) marks the site of crossing over in meiosis.

Q14. In mitosis, which stage shows the shortest duration?
A) Prophase
B) Metaphase
C) Anaphase 
D) Telophase
Answer : C) Anaphase
Concept explanation: Anaphase is very quick because sister chromatids rapidly move to opposite poles.

Q15. At which stage of meiosis does independent assortment occur?
A) Prophase I
B) Metaphase I 
C) Anaphase I
D) Telophase II
Answer : B) Metaphase I 
Concept explanation: In Metaphase I, homologous chromosome pairs line up randomly → independent assortment.

Q16. A cell has 20 chromosomes at G1. What will be the number after S phase?
A) 20
B) 40 DNA molecules (20 chromosomes) 
C) 40 chromosomes
D) 10 chromosomes
Answer : B) 40 DNA molecules (20 chromosomes) 
Concept explanation: After S phase, DNA doubles but chromosomes remain the same (20). Each has two chromatids.

Q17. The term “equational division” is applied to:
A) Mitosis 
B) Meiosis I
C) Meiosis II
D) Amitosis
Answer : A) Mitosis
Concept explanation: In mitosis → chromosome number remains constant.

Q18. Crossing over occurs between:
A) Sister chromatids
B) Non-sister chromatids 
C) Homologous centromeres
D) Spindle fibers
Answer : B) Non-sister chromatids
Concept explanation: Genetic recombination occurs between non-sister chromatids of homologous chromosomes.

Q19. Which of the following structures disappears during prophase?
A) Ribosomes
B) Spindle fibers
C) Nuclear membrane 
D) Chromosomes
Answer : C) Nuclear membrane
Concept explanation: In prophase, nuclear envelope and nucleolus dissolve.

Q20. In humans, primary spermatocyte undergoes meiosis I to form:
A) Two spermatogonia
B) Two secondary spermatocytes 
C) Four spermatids
D) Four sperms
Answer : B) Two secondary spermatocytes
Concept explanation:
Primary spermatocyte (2n) → Meiosis I → Two secondary spermatocytes (n).

Q21. Cytokinesis in plant cells occurs by:
A) Cleavage furrow
B) Cell plate formation 
C) Cell wall rupture
D) Chromosome pull
Answer : B) Cell plate formation
Concept explanation: In plants, cytokinesis occurs by cell plate method (via Golgi vesicles).

Q22. G0 phase represents:
A) DNA synthesis
B) Cell division
C) Dormant phase 
D) Mitosis
Answer : C) Dormant phase
Concept explanation: Cells in G0 phase are metabolically active but not dividing (e.g., neurons, cardiac cells).

Q23. During which phase of mitosis do spindle fibers attach to kinetochores?
A) Prophase
B) Metaphase 
C) Anaphase
D) Telophase
Answer : B) Metaphase
Concept explanation: Spindle fibers attach to kinetochore of centromere during metaphase.
Q24. In which stage of meiosis I do homologous chromosomes separate?
A) Prophase I
B) Metaphase I
C) Anaphase I 
D) Telophase I
Answer : C) Anaphase I 
Concept explanation: In Anaphase I, homologous chromosomes move to opposite poles → reduction occurs.
Q25. The interval between mitotic divisions is called:
A) Interphase 
B) Karyokinesis
C) Cytokinesis
D) Prophase
Answer : A) Interphase
Concept explanation: Interphase is the “gap” between two mitotic cycles.

Last Remarks

The chapter on cell division and the cell cycle effectively illustrates how life maintains itself at the cellular level. The cell cycle's stages, the distinctions between mitosis and meiosis, and significant occurrences like crossing over are all important for NEET.
A quick tip: Since NEET frequently uses image-based questions, make labeled diagrams of the stages of mitosis and meiosis in your notes.


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