Apomixis Polyembryony

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 trap: NEET often tests whether you can distinguish apomixis from vegetative propagation, and whether you know polyembryony produces multiple embryos within a single seed — not multiple seeds.

Apomixis is seed production without fertilisation. The embryo develops from the maternal tissue, so the offspring is a genetic clone of the mother plant. NCERT Class 12 Biology Chapter 1 (page 23) notes that some species like Citrus and grasses in Asteraceae employ apomixis. There are two main mechanisms:

  1. Diplospory — the megaspore mother cell skips meiosis (or undergoes restitution) and directly develops into the embryo sac. No reduction division → diploid egg → embryo without fertilisation.
  2. Apospory — a nucellar cell (somatic, 2n) develops into an embryo sac, bypassing the megaspore mother cell entirely.

In both cases, the endosperm may still require pollination (pseudogamy) — the central cell fuses with a sperm for endosperm development, but the egg cell develops parthenogenetically. This is a common NEET confusion: apomixis does NOT always mean pollination is absent; it means fertilisation of the egg is absent.

Polyembryony is the occurrence of more than one embryo inside a single seed. In Citrus, adventive embryos arise from nucellar cells alongside the sexually-formed zygotic embryo. The result: one seed germinates into multiple seedlings, most of which are maternal clones (nucellar embryos) while one may be the hybrid zygotic embryo.

Why NEET cares: Apomixis is commercially valuable — it can fix hybrid vigour across generations without segregation. If a hybrid variety could reproduce by apomixis, farmers would not need to buy fresh hybrid seeds every season. This application angle appears in assertion-reason and application-type questions.

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

Apomixis is best defined as:

MCQ 2Easy RecallPractice

In apospory, the embryo sac develops from:

MCQ 3Easy RecallPractice

Polyembryony in *Citrus* results from:

MCQ 4Direct ApplicationPractice

A farmer wants to maintain hybrid vigour across generations without purchasing new seeds each year. Which reproductive strategy, if introduced into the crop, would achieve this?

MCQ 5Direct ApplicationPractice

In pseudogamy, pollination is required even though the egg develops without fertilisation. The role of pollination here is to:

MCQ 6Direct ApplicationPractice

A seed of *Citrus* is germinated and produces five seedlings. Four are phenotypically identical to the mother plant and one shows variation. The most likely explanation is:

MCQ 7Concept TrapPractice

Which of the following correctly distinguishes apomixis from vegetative propagation?

MCQ 8Concept TrapPractice

An assertion-reason question:

Worked Example

  1. 1

    Given

    A mango variety shows the following: seeds produce multiple seedlings; most seedlings are genetically identical to the parent tree; one seedling per seed occasionally differs.

  2. 2

    Required

    Identify: (a) the phenomenon, (b) the origin of the identical seedlings, (c) the origin of the variant seedling.

  3. 3

    Concept

    Polyembryony — multiple embryos within a single seed. In many angiosperms (notably *Citrus*, mango), nucellar cells develop into adventive embryos (2n, maternal clones) alongside the sexually-produced zygotic embryo.

  4. 4

    Key principle

    Nucellar embryos = somatic origin = clone of mother. Zygotic embryo = product of fertilisation = genetic recombination possible.

  5. 5

    Application

    - Multiple seedlings from one seed → polyembryony confirmed. - Most identical to parent → these are nucellar (adventive) embryos. - One variant → this is the zygotic embryo (sexual fusion introduced new allele combinations).

  6. 6

    Reasoning

    No formula needed. The reasoning is purely conceptual: adventive embryony from nucellar cells is mitotic (no meiosis, no recombination) → clones. The zygotic embryo underwent meiosis + fertilisation → potential variation.

  7. 7

    Final answer

    (a) Polyembryony. (b) Identical seedlings arise from adventive (nucellar) embryos — maternal clones. (c) The variant seedling is the zygotic embryo formed by sexual fertilisation.

  8. 8

    Common trap

    Confusing polyembryony with "multiple seeds per fruit." Polyembryony is multiple embryos within ONE seed. A fruit with many seeds (e.g., tomato) is NOT polyembryony.

  9. 9

    Similar NEET-style question

    "In *Citrus*, if a seed produces 4 seedlings of which 3 are identical to the mother plant, the 3 identical seedlings most likely developed from: (a) synergids (b) antipodal cells (c) nucellar cells (d) zygote cleavage" — Answer: (c) nucellar cells.

Before solving, remember these

Apomixis: seed without fertilisation (asexual seed). Polyembryony: multiple embryos in one seed (Citrus, mango). Used to fix hybrid vigour for several generations.

-- NCERT Class 12 Biology, Ch. 1, p. 23

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.

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.

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.

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).

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).

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.

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.