Cell Cycle and Cell Division for NEET: Chapter 10 Guide
Cell cycle and cell division is Chapter 10 of the NCERT Class 11 Biology book, and the cell cycle is the sequence of events by which a cell duplicates its genome, builds its other parts and finally divides into two daughter cells. For NEET it means three things: interphase (G1, S, G2), mitosis, and meiosis, plus why each matters. The chapter is short, about 3,700 words, but cell cycle and cell division questions turn on exact counts: how many chromosomes, how much DNA, which sub-stage. This guide sets those out the way the exam asks them.
What is cell cycle and cell division?
Cell division is the process by which one parent cell gives rise to two daughter cells, and the cell cycle is the full sequence of growth, DNA replication and division that a cell passes through between one division and the next. NCERT stresses that all three, cell growth, DNA synthesis and division, must run in a coordinated way so that every daughter cell gets an intact genome.
Two details from the opening section of the NCERT chapter on cell cycle and cell division are worth fixing in memory. Cell growth, in terms of cytoplasmic increase, is continuous. DNA synthesis is not: it happens only in one specific stage. Questions like to flip that around.
The genome.gov definition of the cell cycle from the US National Human Genome Research Institute puts it the same way: a cell spends most of its time in interphase, growing and copying its chromosomes, then leaves interphase, goes through mitosis and completes its division.
Where does cell cycle and cell division sit in the NEET syllabus?
It is the third bullet of Unit 3, Cell Structure and Function, in the NMC syllabus for NEET (UG) 2026, worded as "Cell division: Cell cycle, mitosis, meiosis and their significance". Unit 3 maps to three NCERT Class 11 chapters: Chapter 8 (Cell: The Unit of Life), Chapter 9 (Biomolecules) and Chapter 10.
The NMC syllabus notice of 22 December 2025 is the document NTA's 2026 bulletin points to. It does not give marks for cell cycle and cell division or any other chapter, and nor does NTA, so treat any "guaranteed questions from this chapter" figure you see online as an estimate, not a fact. What NTA does fix is the paper: Biology carries 90 of the 180 questions and 360 of the 720 marks, and every question is +4 for right, -1 for wrong and 0 if left blank, per the NEET (UG) 2026 Information Bulletin.
| Syllabus phrase | NCERT section | What gets asked |
|---|---|---|
| Cell cycle | 10.1, 10.1.1 | Phases, durations, G0, 2C to 4C |
| Mitosis | 10.2.1 to 10.2.5 | Events of each stage, cytokinesis in plants vs animals |
| Significance of mitosis | 10.3 | Growth, repair, nucleo-cytoplasmic ratio |
| Meiosis | 10.4, 10.4.1, 10.4.2 | Five sub-stages of prophase I, anaphase I vs II |
| Significance of meiosis | 10.5 | Constant chromosome number, variation |
Unit 3 also contains Biomolecules, which the biomolecules guide for NEET covers, and the full unit-by-unit picture is in the NEET Biology syllabus explainer. If you want to see how this unit compares with the others by reading load, future-mbbs.com has a chapter-wise weightage breakdown for NEET 2027.
What are the phases of the cell cycle?
The cell cycle has two basic phases: interphase and M phase (the mitosis phase). Interphase is split into G1 (Gap 1), S (Synthesis) and G2 (Gap 2). M phase is split into karyokinesis, the division of the nucleus, and cytokinesis, the division of the cytoplasm. NCERT calls interphase the "resting phase", then immediately explains that it is anything but resting. Most cell cycle and cell division questions start here, with the phase table below.
Here is what happens in each part, in NCERT's own terms:
| Phase | What happens | DNA content | Chromosome number |
|---|---|---|---|
| G1 | Cell is metabolically active and keeps growing, no DNA replication | 2C | 2n |
| S | DNA replication; in animal cells the centriole also duplicates in the cytoplasm | 2C to 4C | 2n |
| G2 | Proteins made in preparation for mitosis, growth continues | 4C | 2n |
| M | Karyokinesis, then cytokinesis | 4C back to 2C in each daughter | 2n in each daughter |
NCERT gives the numbers that sit behind the chart: human cells in culture divide roughly once every 24 hours, yeast can go through the cycle in about 90 minutes, and the duration varies between organisms and between cell types. The 24-hour figure is the answer to Exercise 1 ("What is the average cell cycle span for a mammalian cell?").
What is the G0 phase?
G0, the quiescent stage, is where cells go when they stop dividing. They exit G1 and stay metabolically active, but no longer proliferate unless the organism calls on them to. NCERT's example is heart cells in adult animals, which do not appear to divide, while many other cells divide only occasionally to replace cells lost to injury or death.
What happens in each stage of mitosis?
Mitosis is the equational division: the parent cell and the daughter cells have the same number of chromosomes. Karyokinesis has four stages, prophase, metaphase, anaphase and telophase, and NCERT warns that they are a continuous process with no clear-cut lines between them. Questions still pin each event to one stage.
- Prophase. Chromosomal material condenses into compact mitotic chromosomes, each made of two chromatids joined at the centromere. The centrosome, duplicated in interphase, moves towards opposite poles and sends out asters; asters plus spindle fibres form the mitotic apparatus. By the end, Golgi complexes, ER, the nucleolus and the nuclear envelope are no longer visible.
- Metaphase. It starts with the complete disintegration of the nuclear envelope. Condensation is complete, so this is the best stage to study chromosome morphology. Spindle fibres attach to kinetochores, the small disc-shaped structures on the centromeres, and the chromosomes line up on the metaphase plate.
- Anaphase. Centromeres split, and the sister chromatids, now called daughter chromosomes, move to opposite poles, centromere first with the arms trailing behind.
- Telophase. Chromosomes reach the poles, decondense and lose their individuality. A nuclear envelope forms around each cluster, and the nucleolus, Golgi complex and ER reform.
- Cytokinesis. The cytoplasm divides. Animal cells form a furrow in the plasma membrane that deepens until it meets in the centre. Plant cells, held in by a rigid wall, build a cell plate from the centre outwards, which becomes the middle lamella between the two new walls.
One exception from the mitosis half of cell cycle and cell division gets asked often: sometimes karyokinesis is not followed by cytokinesis, which gives a multinucleate condition called a syncytium. NCERT's example is the liquid endosperm in coconut.
If you need to draw these stages, the NEET Biology diagrams guide lists which NCERT figures are worth practising by hand.
Why is mitosis important?
Mitosis matters because it makes diploid daughter cells with an identical genetic complement. NCERT gives four uses: growth of multicellular organisms, restoring the nucleo-cytoplasmic ratio after a cell grows, cell repair (the upper epidermis, the gut lining and blood cells are constantly replaced), and continuous plant growth from the apical and lateral meristems.
Who divides by mitosis is its own question. In animals, mitosis is seen only in diploid somatic cells, with exceptions such as male honey bees, whose haploid cells divide by mitosis. Plants show mitosis in both haploid and diploid cells. The Plant Kingdom guide covers alternation of generations, which is where the haploid examples come from.
What are the stages of meiosis?
Meiosis is the reduction division that halves the chromosome number to make haploid gametes. It runs two divisions, meiosis I and meiosis II, after only one round of DNA replication, and it ends with four haploid cells. Its defining events are the pairing of homologous chromosomes and recombination between their non-sister chromatids.
The genome.gov entry on meiosis gives the human numbers that make the point: body cells are diploid with 46 chromosomes, and each egg or sperm must carry 23, so that fertilisation restores 46.
What are the five stages of prophase I?
Prophase I is longer and more complex than the prophase of mitosis, and it is where most meiosis questions in cell cycle and cell division come from. Each sub-stage has one event you must link to it:
| Sub-stage | Key event | Remember it by |
|---|---|---|
| Leptotene | Chromosomes become gradually visible and keep compacting | Chromosomes appear |
| Zygotene | Synapsis: homologous chromosomes pair; synaptonemal complex forms; the pair is a bivalent or tetrad | Pairing |
| Pachytene | Four chromatids of each bivalent become distinct; recombination nodules appear; crossing over by the enzyme recombinase | Crossing over |
| Diplotene | Synaptonemal complex dissolves; homologues start to separate except at chiasmata, the X-shaped structures; can last months or years in oocytes of some vertebrates | Chiasmata seen |
| Diakinesis | Chiasmata terminalise; chromosomes fully condensed; spindle assembles; nucleolus disappears and nuclear envelope breaks down | Transition to metaphase I |
A memory line many students use: "Lazy Zebras Prefer Drinking Daily", one word per sub-stage in order.
What happens after prophase I?
- Metaphase I. Bivalents line up on the equatorial plate, with spindle fibres from opposite poles attached to the kinetochores of homologous chromosomes.
- Anaphase I. Homologous chromosomes separate. Sister chromatids stay together at their centromeres.
- Telophase I. Nuclear membrane and nucleolus reappear and cytokinesis gives a dyad of cells.
- Interkinesis. A short gap between the two divisions, with no DNA replication.
- Meiosis II. It resembles a normal mitosis. In anaphase II the centromere of each chromosome finally splits and the sister chromatids move apart. Telophase II ends with a tetrad of four haploid cells.
Meiosis is significant for two reasons, both in section 10.5: it keeps the chromosome number of a species constant across generations, and it increases genetic variability from one generation to the next. That variation feeds straight into the genetics chapters for NEET, and the way meiosis makes sperm and eggs is the core of the human reproduction guide.
How do chromosome number and DNA content change through the cycle?
This is the calculation behind NCERT's margin question and Exercise 16, and in cell cycle and cell division it is easy marks once you see the rule. Chromosome number (n) changes only when chromosomes are shared out between cells. DNA content (C) doubles in S phase and halves at each division. Take NCERT's onion root tip, with 16 chromosomes per cell and 2C after M phase:
| Stage | Chromosomes per cell | DNA content per cell |
|---|---|---|
| G1 | 16 | 2C |
| After S phase | 16 | 4C |
| G2 | 16 | 4C |
| After mitosis (each daughter) | 16 | 2C |
Now apply the same rule to meiosis in a 2n cell. After S phase it is 2n and 4C. After meiosis I each cell is n with 2C, because whole homologues have gone to each pole. After meiosis II each of the four cells is n with 1C. If an option says DNA halves in S phase or chromosomes double in S phase, it is wrong.
How is mitosis different from meiosis?
Mitosis keeps the chromosome number and produces two genetically identical cells, while meiosis halves the chromosome number and produces four genetically varied haploid cells. Mitosis serves growth and repair; meiosis serves sexual reproduction. Both start after one S phase, but meiosis divides twice.
| Point | Mitosis | Meiosis |
|---|---|---|
| Type of division | Equational | Reductional (meiosis I), then equational (meiosis II) |
| Number of divisions | One | Two |
| Daughter cells | Two, diploid, identical | Four, haploid, varied |
| Pairing of homologues | No | Yes, in zygotene |
| Crossing over | No | Yes, in pachytene |
| What separates in anaphase | Sister chromatids | Homologues in anaphase I, sister chromatids in anaphase II |
| Where it happens | Somatic cells (diploid in animals) | Cells that form gametes |
Exercise 10, "Distinguish anaphase of mitosis from anaphase I of meiosis", is answered by one row of that table. Exercise 11 of cell cycle and cell division, "List the main differences between mitosis and meiosis", is the whole table.
Eight traps in cell cycle and cell division questions
Most wrong answers in cell cycle and cell division come from the same few swaps.
- "Interphase is a resting phase." NCERT uses the phrase, then says the cell is preparing for division through growth and DNA replication. Read the option to the end.
- DNA vs chromosome count in S phase. DNA doubles from 2C to 4C; the chromosome number stays at 2n.
- Where the centriole duplicates. In animal cells, DNA replication begins in the nucleus during S phase while the centriole duplicates in the cytoplasm.
- The marker of metaphase. At the end of prophase the nuclear envelope is no longer visible; NCERT says its complete disintegration marks the start of metaphase.
- Pachytene vs diplotene. Crossing over and recombination nodules: pachytene. Visible chiasmata after the synaptonemal complex dissolves: diplotene.
- Anaphase I vs anaphase II. Homologues separate in anaphase I; centromeres split only in anaphase II.
- Interkinesis. There is no DNA replication between meiosis I and meiosis II.
- Coconut. Liquid endosperm is a syncytium: karyokinesis without cytokinesis.
A four-day revision plan for this chapter
- Day 1: Read sections 10.1 and 10.2 of NCERT cell cycle and cell division with the figures open. Write the phase table and the G0 definition from memory.
- Day 2: Read sections 10.3 to 10.5. Make the prophase I table yourself and say each key event out loud.
- Day 3: Work NCERT Exercises 1 to 16 in writing, especially 6, 10, 11 and 16. Do the chromosome and DNA table for both mitosis and meiosis without looking.
- Day 4: Solve a timed set of chapter questions, then mark every wrong answer against the eight traps above. Our [NEET Biology MCQ guide](/blogs/neet-biology-mcq/) explains how to review a set, and the [negative marking explainer](/blogs/neet-negative-marking/) covers when to leave a question blank.
NCERT is the base for cell cycle and cell division, as for every NEET Biology chapter. If you are deciding how far beyond the textbook to read, future-mbbs.com explains what the NCERT books are and how to use them, and keeps the full NEET syllabus across all three subjects on one page.
Sources
Every fact about cell cycle and cell division above comes from these official documents, all opened and read on 11 November 2026.
- NCERT, Biology Textbook for Class XI, Chapter 10 "Cell Cycle and Cell Division", reprint 2026-27 (sections 10.1 to 10.5, summary and exercises): https://ncert.nic.in/textbook/pdf/kebo110.pdf
- National Medical Commission, Under Graduate Medical Education Board, "Updated syllabus for NEET(UG)-2026", 22 December 2025 (Biology Unit 3, Cell Structure and Function): https://cdnbbsr.s3waas.gov.in/s37bc1ec1d9c3426357e69acd5bf320061/uploads/2026/01/202601081066816297.pdf
- National Testing Agency, Information Bulletin NEET (UG) 2026 (pattern of the test and marking scheme): https://cdnbbsr.s3waas.gov.in/s37bc1ec1d9c3426357e69acd5bf320061/uploads/2026/02/202602231394640855.pdf
- National Human Genome Research Institute, Talking Glossary of Genomic and Genetic Terms, "Cell Cycle": https://www.genome.gov/genetics-glossary/Cell-Cycle
- National Human Genome Research Institute, Talking Glossary of Genomic and Genetic Terms, "Meiosis": https://www.genome.gov/genetics-glossary/Meiosis
Frequently Asked Questions
The cell cycle is the sequence of events by which a cell duplicates its genome, makes its other parts and divides into two daughter cells. Cell division is the dividing step itself. NCERT splits the cycle into interphase (G1, S, G2) and M phase, and a human cell in culture completes one cycle in about 24 hours.
For mitosis, the four stages of karyokinesis are prophase, metaphase, anaphase and telophase, followed by cytokinesis, the division of the cytoplasm. NCERT adds that division is a continuous process and the boundaries between stages are not clear-cut, but NEET questions still tie each event to one stage.
NCERT Class 11 Chapter 10 describes two types: mitosis, the equational division, and meiosis, the reduction division. Some books add amitosis as a third type, but the NCERT chapter does not mention it, so NEET preparation should centre on mitosis and meiosis.
G0 is the quiescent stage. Cells that stop dividing exit G1 and enter G0, where they stay metabolically active but no longer proliferate unless the organism needs them to. NCERT gives heart cells in adult animals as the example of cells that do not appear to divide.
Mitosis is one division that gives two diploid, genetically identical cells for growth and repair. Meiosis is two divisions after one DNA replication that give four haploid, genetically varied cells for gamete formation. Only meiosis has homologue pairing in zygotene and crossing over in pachytene.
Yes. It is named in Unit 3 of the NMC syllabus for NEET (UG) 2026 as cell cycle, mitosis, meiosis and their significance, and Biology carries 360 of the 720 marks. NTA does not publish marks per chapter, but the chapter is short and fact-dense, which makes it efficient to revise.
If you are revising Class 11 Biology for NEET, NEETsheet is our prep app for NCERT-aligned question sets and timed mocks, so you can see which chapters, this one included, are still costing you marks. Find it at neetsheet.in.
