Menstrual Cycle

8 MCQs9-step worked example
Source: NCERT Anatomy of Flowering PlantsPYQ coverage: NEET 2020, 2021, 2022, 2023, 2024, 2025Official key: NTA-verifiedLast reviewed: May 2026

Lesson

The single trap that costs marks in menstrual cycle questions: swapping which hormone dominates which phase. FSH and progesterone sound equally "hormonal," and under pressure aspirants assign them to the wrong half of the 28-day cycle.

The menstrual cycle averages 28 days and divides into four overlapping events (NCERT Class 12 Biology Chapter 2, page 40):

  1. Menstrual phase (Days 1–5): Endometrium sheds. Progesterone and estrogen are at their lowest. FSH begins rising.

  2. Follicular (proliferative) phase (Days 6–13): FSH from the anterior pituitary stimulates growth of ovarian follicles. The growing follicle secretes estrogen, which rebuilds the endometrium and inhibits FSH via negative feedback — but also primes the hypothalamus for positive feedback at high concentrations.

  3. Ovulation (Day 14): A sharp LH surge (triggered by peak estrogen via positive feedback on GnRH/LH) ruptures the Graafian follicle, releasing the secondary oocyte.

  4. Luteal (secretory) phase (Days 15–28): The ruptured follicle transforms into the corpus luteum, which secretes progesterone (dominant hormone) and some estrogen. Progesterone maintains the thickened endometrium and inhibits GnRH/FSH/LH. If no fertilisation occurs, the corpus luteum degenerates → progesterone drops → endometrium sheds → cycle resets.

The high-frequency trap: Questions give you a day number (e.g., "Day 20") and ask which hormone is dominant. Map it: Days 1–13 = follicular = FSH-driven (estrogen rising). Day 14 = LH peak. Days 15–28 = luteal = progesterone-dominant. Confusing LH surge with FSH dominance, or placing progesterone in the follicular phase, is the mark-losing error NTA exploits.

Practice MCQs

Select an option to see the explanation. Wrong answers show why your choice was tempting — and name the exact trap it exploits.

MCQ 1Easy RecallPractice

Which hormone is primarily responsible for the proliferation of endometrium during the follicular phase of the menstrual cycle?

MCQ 2Easy RecallPractice

On approximately which day of a typical 28-day menstrual cycle does ovulation occur?

MCQ 3Easy RecallPractice

The corpus luteum secretes which of the following hormones to maintain the endometrium during the luteal phase?

MCQ 4Direct ApplicationPractice

During the menstrual cycle, a high concentration of estrogen near the end of the follicular phase triggers a surge of LH via:

MCQ 5Direct ApplicationPractice

If the corpus luteum degenerates without fertilisation, which sequence of events follows?

MCQ 6Direct ApplicationPractice

A woman's blood sample taken on Day 22 of her cycle shows a high level of progesterone and low FSH. This hormonal profile indicates she is in the:

MCQ 7Concept TrapPractice

During the follicular phase, FSH promotes follicle growth. The growing follicle produces estrogen, which at moderate levels inhibits further FSH secretion. This is an example of:

MCQ 8CalculationPractice

Consider a 28-day menstrual cycle. The endometrium is at its maximum thickness and glandular activity on Day 24. Which TWO conditions must both be true for this to occur?

Worked Example

  1. 1

    Given

    A woman on Day 18 of her menstrual cycle shows a thickened, glandular endometrium with increased blood supply.

  2. 2

    Required

    Identify the dominant hormone responsible for this endometrial state and the ovarian structure producing it.

  3. 3

    Concept

    The menstrual cycle phases map hormones to days: follicular phase (Days 1–13, FSH/estrogen-driven), ovulation (Day 14, LH surge), luteal phase (Days 15–28, progesterone-dominant from corpus luteum).

  4. 4

    Formula/Rule

    Day number → Phase → Dominant hormone → Source structure. Day 18 falls in Days 15–28 → Luteal phase → Progesterone → Corpus luteum.

  5. 5

    Substitution

    Day 18 ∈ [15, 28] → Luteal phase confirmed. Endometrial maintenance + glandular secretion = hallmark of progesterone action. Source = corpus luteum (transformed from ruptured Graafian follicle post-Day 14).

  6. 6

    Calculation

    No numerical calculation. Logical mapping: - Phase identification: 18 > 14 → post-ovulatory → luteal ✓ - Hormone: progesterone (not estrogen, which drives proliferation in follicular phase) ✓ - Structure: corpus luteum (not follicle — follicle already ruptured) ✓

  7. 7

    Final answer

    The dominant hormone is **progesterone**, secreted by the **corpus luteum**.

  8. 8

    Common trap

    Aspirants confuse the proliferative effect of estrogen (rebuilding endometrium in follicular phase) with the secretory/maintenance effect of progesterone (glandular transformation in luteal phase). Both thicken the endometrium — but the mechanism and phase differ. NEET exploits this by describing "thickened endometrium" and offering estrogen as a distractor for luteal-phase questions.

  9. 9

    Similar NEET-style question

    "On Day 25, a blood test shows high progesterone and low LH. Which ovarian structure is responsible for this hormonal profile? (A) Graafian follicle (B) Corpus luteum (C) Primary follicle (D) Corpus albicans." Answer: B — the corpus luteum secretes progesterone during the luteal phase; corpus albicans is the degenerated remnant that no longer secretes hormones. ---

Before solving, remember these

Key Fact

Menstrual cycle

28-day cycle with 4 phases: menstrual (1-5), follicular/proliferative (6-13), ovulatory (14 — LH surge), luteal/secretory (15-28). FSH → follicle growth, LH → ovulation + corpus luteum (progesterone). Estrogen + progesterone feedback.

-- NCERT Class 12 Biology, Ch. 2, p. 40

Exam Traps & Common Mistakes

These are the exact patterns that cause wrong answers in NEET. Each trap includes when it triggers and how to avoid it.

Trap

Contraceptive method category confusion

Category: Similar Terms

Hormonal: pills, implants. Barrier: condom, diaphragm. IUD: Cu releasing (CuT), hormonal (LNG-20). Surgical: vasectomy/tubectomy.

When it triggers

Question asks which category a specific method falls in.

How to avoid

Map by mechanism: hormone → pill/implant; physical block → barrier; uterine → IUD; permanent → surgical.

Trap

Implantation day confusion

Category: Negative Marking

Fertilisation in ampulla; cleavage during journey; implantation occurs ~6-7 days after fertilisation in uterine endometrium.

When it triggers

Question on day of implantation, location of fertilisation.

How to avoid

Fertilisation = ampulla. Implantation = day 6-7 post-fertilisation in uterus.

Trap

Menstrual cycle phase hormones swapped

Category: Similar Terms

FSH dominant follicular phase; LH surge triggers ovulation Day 14; progesterone dominant in luteal phase.

When it triggers

Question gives day or phase and asks dominant hormone.

How to avoid

Follicular = FSH. Day 14 = LH peak. Luteal = progesterone (corpus luteum).

Trap

Spermatogenesis vs oogenesis product confusion

Category: Similar Terms

Spermatogenesis: 1 spermatogonium → 4 sperm (all functional). Oogenesis: 1 oogonium → 1 functional ovum + 3 polar bodies.

When it triggers

Question on number of functional gametes per primary cell.

How to avoid

Sperm: 4. Ovum: 1 (with 3 polar bodies discarded).

Mistake

Says oogenesis produces 4 ova per oogonium.

Root cause: term confusion

Correction

Oogenesis yields ONLY 1 functional ovum + 3 (or 1 + 2) polar bodies that degenerate. Asymmetric cytokinesis preserves cytoplasm in the egg.

Past Year Questions

48 questions from NEET 2020, 2021, 2022, 2023, 2024, 2025. Answers verified against NTA official keys.

NEET 2025

Consider the following : A. The reductive division for the human female gametogenesis starts earlier than that of the male gametogenesis. B. The gap between the first meiotic division and the second meiotic division is much shorter for males compared to females. C. The first polar body is associated with the formation of the primary oocyte. D. Luteinizing Hormone (LH) surge leads to disintegration of the endometrium and onset of menstrual bleeding. Choose the correct answer from the options given below:

1B and C are true
2A and B are true
3A and C are true
4B and D are true
NTA Answer: Option 2(final)
NEET 2025

Given below are two statements : One is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A) : Both wind and water pollinated flowers are not very colourful and do not produce nectar. Reason (R) : The flowers produce enormous amount of pollen grains in wind and water pollinated flowers. In the light of the above statements, choose the correct answer from the options given below:

1A is false but R is true
2Both A and R are true and R is the correct explanation of A
3Both A and R are true but R is NOT the correct explanation of A
4A is true but R is false
NTA Answer: Option 3(final)
NEET 2025

Given below are two statements: Statement I: In a floral formula stands for zygomorphic nature of the flower, and G stands for inferior ovary. Statement II: In a floral formula stands for actinomorphic nature of the flower and G stands for superior ovary. In the light of the above statements, choose the correct answer from the options given below:

1Statement I is incorrect but Statement II is correct
2Both Statement I and Statement II are correct
3Both Statement I and Statement II are incorrect
4Statement I is correct but Statement II is incorrect
NTA Answer: Option 1(final)
NEET 2024

Identify the set of correct statement: A. The flowers of Vallisneria are colourful and produce nectar. B. The flowers of waterlily are not pollinated by water. C. In most of water-pollinated species, the pollen grains are protected from wetting. D. Pollen grains of some hydrophytes are long and ribbon like. E. In some hydrophytes, the pollen grains are carried passively inside water. Choose the correct answer from the options given below.

1C, D and E only
2A, B, C and D only
3A, C, D and E only
4B, C, D and E only
NTA Answer: Option 4(final)
NEET 2024

Identify the correct description about the given figure:

1Wind pollinated plant inflorescence showing flowers with well exposed stamens.
2Water pollinated flowers showing stamens with mucilaginous covering.
3Cleistogamous flowers showing autogamy.
4Compact inflorescence showing complete autogamy
NTA Answer: Option 1(final)
NEET 2024

Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R : Assertion A : FSH acts upon ovarian follicles in female and Leydig cells in male. Reason R : Growing ovarian follicles secrete estrogen in female while interstitial cells secrete androgen in male human being. In the light of the above statements, choose the correct answer from the options given below :

1Both A and R are true and R is the correct explanation of A
2Both A and R are true but R is NOT the correct explanation of A
3A is true but R is false
4A is false but R is true
NTA Answer: Option 4(final)
NEET 2023

Given below are two statements: one is labelled as Assertion A and other is labelled as Reason R. Assertion A : Amniocentesis for sex determination is one of the strategies of Reproductive and Child Health Care Programme. Reason R : Ban on amniocentesis checks increasing menace of female foeticide. In the light of the above statements, choose the correct answer from the options given below.

1Both A and R are true and R is NOT the correct explanation of A.
2A is true but R is false.
3A is false but R is true.
4Both A and R are true and R is the correct explanation of A.
NTA Answer: Option 3(final)
NEET 2023

Which of the following statements are correct regarding female reproductive cycle? A. In non-primate mammals cyclical changes during reproduction are called oestrus cycle. B. First menstrual cycle begins at puberty and is called menopause. C. Lack of menstruation may be indicative of pregnancy. D. Cyclic menstruation extends between menarche and menopause. Choose the most appropriate answer from the options given below.

1A and B only
2A, B and C only
3A, C and D only
4A and D only
NTA Answer: Option 3(final)
NEET 2023

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R. Assertion A: Endometrium is necessary for implantation of blastocyst. Reason R: In the absence of fertilization, the corpus luteum degenerates that causes disintegration of endometrium. In the light of the above statements, choose the correct answer from the options given below:

1Both A and R are true but R is NOT the correct explanation of A.
2A is true but R is false.
3A is false but R is true.
4Both A and R are true and R is the correct explanation of A.
NTA Answer: Option 1(final)
NEET 2022

Identify the incorrect statement related to Pollination :

1Moths and butterflies are the most dominant pollinating agents among insects
2Pollination by water is quite rare in flowering plants
3Pollination by wind is more common amongst abiotic pollination
4Flowers produce foul odours to attract flies and beetles to get pollinated
NTA Answer: Option 1(final)
NEET 2022

Given below are two statements : Statement I : Cleistogamous flowers are invariably autogamous Statement II : Cleistogamy is disadvantageous as there is no chance for cross pollination In the light of the above statements, choose the correct answer from the options given below :

1Statement I is incorrect but Statement II is correct
2Both Statement I and Statement II are correct
3Both Statement I and Statement II are incorrect
4Statement I is correct but Statement II is incorrect
NTA Answer: Option 2(final)
NEET 2022

Given below are two statements: Statement I : The release of sperms into the seminiferous tubules is called spermiation. Statement II : Spermiogenesis is the process of formation of sperms from spermatogonia. In the light of the above statements, choose the most appropriate answer from the options given below :

1Statement I is incorrect but Statement II is correct
2Both Statement I and Statement II are correct
3Both Statement I and Statement II are incorrect
4Statement I is correct but Statement II is incorrect
NTA Answer: Option 4(final)
NEET 2021

Match List-I with List-II.

1(iv) (ii) (i) (iii)
2(iv) (i) (iii) (ii)
3(iii) (i) (iv) (ii)
4(ii) (iii) (iv) (i)
NTA Answer: Option 3(final)
NEET 2021

Which of the following statements of incorrect? 148. Match List-I with List-II.

1Oxidation-reduction reactions produce proton List-I List-II gradient in respiration (a) Protein (i) C = C double bonds
2During aerobic respiration, role is oxygen is (b) Unsaturated (ii) Phosphodiester limited to the terminal state fatty acid bonds (c) Nucleic acid (iii) Glycosidic bonds
3In ETC (Electron Transport Chain), one molecule of NADH + H+ gives rise to 2 ATP molecules, (d) Polsyaccharide(iv) Peptide bonds and one FADH gives rise to 3 ATP molecules 2 (a) (b) (c) (d)
4ATP is synthesized through complex V (1) (iv) (iii) (i) (ii)
NTA Answer: Option 3(final)
NEET 2021

Which of the following is not a step in Multiple (4) (b) and (c) only Ovulation Embryo Transfer Technology (MOET)?

1Fertilized eggs are transferred to surrogate Answer (4) mothers at 8-32 cell stage 197. Following are the statements about prostomium of
2Cow is administered hormone having LH like earthworm. activity for super ovulation (a) It serves as a covering for mouth.
3Cow yields about 6-8 eggs at a time (b) It helps to open cracks in the soil into which it
4Cow is fertilized by artifical insemination can crawl.
NTA Answer: Option 2(final)
NEET 2020

¬ÊŒ¬ ∑§Ê fl„ ÷ʪ ∑§ÊÒŸ-‚Ê „Ò Á¡‚◊ ŒÊ ¬Ë…∏Ë - ∞∑§ ¬Ë…∏Ë 92. The plant parts which consist of two generations - one within the other : ŒÍ‚⁄ U ∑ § •ãŒ⁄U „Ê ÃË „Ò? (a) Pollen grains inside the anther (a) ¬⁄Uʪ∑§Ê ‡Ê ∑ § •ãŒ⁄U ¬⁄Uʪ∑§áÊ (b) ŒÊ Ÿ⁄U ÿÈÇ◊∑§Ê flÊ‹Ë • ∑ȧÁ⁄Uà ¬⁄Uʪ∑§áÊ (b) Germinated pollen grain with two male gametes (c) »§‹ ∑ § •ãŒ⁄U ’Ë¡ (d) ’Ë¡Êá«U ∑ § •ãŒ⁄U ÷Í˝áÊ-∑§Ê (c) Seed inside the fruit

1(a) •Ê⁄Ò U (d) (d) Embryo sac inside the ovule
2∑ §fl‹ (a) (1) (a) and (d)
3(a), (b) •ÊÒ⁄U (c) (2) (a) only
4(c) •ÊÒ⁄U (d) (3) (a), (b) and (c) (4) (c) and (d)
NTA Answer: Option 1(final)
NEET 2020

ÿÊÒŸ ‚ øÁ⁄Uà ⁄UÊ ªÊ ∑ § ‚„Ë Áfl∑§À¬ ∑§Ê øÿŸ ∑§⁄UÊ – 99. Select the option including all sexually transmitted

1∑Ò §‚⁄U, AIDS, Á‚Á»§Á‹‚ diseases.
2‚È¡Ê∑§, Á‚Á»§Á‹‚, ¡ŸÁŸ∑§ ¬Á⁄U‚¬¸ (1) Cancer, AIDS, Syphilis
3‚È¡Ê∑§, ◊‹ Á⁄UÿÊ, ¡ŸÁŸ∑§ ¬Á⁄U‚¬¸ (2) Gonorrhoea, Syphilis, Genital herpes
4AIDS, ◊‹ Á⁄UÿÊ, »§Êß‹ Á⁄UÿÊ (3) Gonorrhoea, Malaria, Genital herpes (4) AIDS, Malaria, Filaria
NTA Answer: Option 2(final)
NEET 2020

ÁŸêŸ ⁄UÊ ªÊ ∑§Ê ©Ÿ∑ § ¬ÒŒÊ ∑§⁄UŸ flÊ‹ ¡ËflÊ ∑ § ‚ÊÕ Á◊‹ÊŸ ∑§⁄U 109. Match the following diseases with the causative organism and select the correct option. ‚„Ë Áfl∑§À¬ ∑§Ê øÿŸ ∑§⁄UÊ – Column - I Column - II Sà ÷ - I Sà ÷ - II (a) ≈UÊß»§ÊÚß«U (i) flÈø ⁄ UÁ⁄UÿÊ (a) Typhoid (i) Wuchereria (b) ãÿÍ◊Ê ÁŸÿÊ (ii) å‹Òí◊Ê Á«Uÿ◊ (b) Pneumonia (ii) Plasmodium (c) »§Êß‹ Á⁄U∞Á‚‚ (iii) ‚ÊÀ◊Ê Ÿ ‹Ê (c) Filariasis (iii) Salmonella (d) ◊‹ Á⁄UÿÊ (iv) „Ë◊Ê Á»§‹‚ (d) Malaria (iv) Haemophilus (a) (b) (c) (d) (a) (b) (c) (d)

1(iv) (i) (ii) (iii) (1) (iv) (i) (ii) (iii)
2(i) (iii) (ii) (iv) (2) (i) (iii) (ii) (iv)
3(iii) (iv) (i) (ii) (3) (iii) (iv) (i) (ii)
4(ii) (i) (iii) (iv) (4) (ii) (i) (iii) (iv)
NTA Answer: Option 3(final)

How NEET usually asks this

Recurring question shapes from past papers. Each pattern shows why wrong options look tempting.

Sources

NCERT refs: Class 12 Biology Chapter 2, p.40

Test yourself on this topic with real past-paper questions:

Practice this topic →

Free NEET study resources

Get a structured 30-day study plan and a complete formula booklet — delivered to your inbox instantly.