Reproduction in Flowering Plants – Notes, MCQs and NEET Questions

Flowering plants, also known as angiosperms, primarily reproduce sexually. This process involves the production of male and female gametes and their fusion, leading to seed and fruit formation. Understanding this topic is important for many competitive exams, including NEET. Here, we will explore the key steps, terminology, and multiple-choice questions to help you gain a thorough understanding of reproduction in flowering plants.

Key Steps in Sexual Reproduction

1. Pollination: The transfer of pollen grains from the anther (male part) to the stigma (female part).

2. Pollen Germination: Once on a compatible stigma, the pollen grain germinates to form a pollen tube, which carries the male gametes towards the ovule.

3. Fertilisation: Fusion of male and female gametes. In angiosperms, this includes double fertilisation (formation of zygote and endosperm).

4. Embryo and Seed Formation: After fertilisation, the fertilised ovule develops into a seed containing the embryo, and the ovary matures into a fruit.

Formation of Male and Female Gametophytes

• Male Gametophyte (Pollen Grain)

• Develops within the anther.

• Each pollen grain typically has two nuclei: the tube nucleus (which helps form the pollen tube) and the generative nucleus (which divides to form two male gametes).

• Female Gametophyte (Embryo Sac)

• Develops within the ovule.

• A single functional megaspore undergoes divisions to form the embryo sac, which contains the egg cell and other nuclei essential for fertilisation and endosperm formation.

Pollination and Fertilisation

• Types of Pollination:

• Self-pollination (Autogamy): Pollen from the anther lands on the stigma of the same flower.

• Cross-pollination (Xenogamy): Pollen is transferred to a stigma of a different plant of the same species.

• Geitonogamy: Pollen transfer from the anther of one flower to the stigma of another flower on the same plant. Though genetically similar to self-pollination, it often requires pollinators.

• Double Fertilisation:

• One male gamete fuses with the egg cell to form the zygote (2n).

• The other male gamete fuses with two polar nuclei to form the triploid endosperm (3n).

• This ensures efficient use of resources and provides nourishment for the developing embryo.

Significance of Double Fertilisation

1. Efficient Resource Use: Endosperm develops only if fertilisation occurs, preventing wastage of nutrients.

2. Enhanced Seed Viability: The triploid endosperm provides a rich nutrient reserve for the embryo.

3. Unique to Angiosperms: This process sets flowering plants apart from other plant groups.

Common NEET Questions on Sexual Reproduction in Flowering Plants

When preparing for sexual reproduction in flowering plants NEET questions, focus on:

• Structure and function of flower parts (stamen, pistil, petals, sepals).

• Types of pollination and agents of pollination (wind, water, insects).

• Male and female gametophyte development.

• Double fertilisation mechanism and its significance.

• Seed and fruit formation, parthenocarpy, apomixis.

These topics often appear in NEET, and understanding them clearly will help you answer both direct and concept-based questions.

Multiple Choice Questions on Reproduction in Flowering Plants

Test your understanding with these MCQs. Answers are provided in the Answer Key section.

1. Flowers that possess both androecium and gynoecium (male and female parts) are called:
   A. Bisexual flowers
   B. Anther
   C. Stamens
   D. Unisexual flowers

2. The transfer of pollen grains from the anther to the stigma is termed:
   A. Pollination
   B. Fertilisation
   C. Adoption
   D. Diffusion

3. The fusion of the female reproductive nucleus with the male reproductive nucleus is known as:
   A. Adoption
   B. Excretion
   C. Fertilisation
   D. Regeneration

4. The two nuclei initially present at the tip of the pollen tube are:
   A. Tube nucleus and a generative nucleus
   B. Sperm and ovum
   C. Generative nucleus and stigma
   D. Tube nucleus and sperm

5. The generative nucleus in a pollen grain divides to form:
   A. Two male nuclei
   B. Three male nuclei
   C. Two female nuclei
   D. Three female nuclei

6. The embryo sac is located in the:
   A. Stigma
   B. Ovule
   C. Micropyle
   D. Style

7. One of the male nuclei from the pollen tube fuses with the secondary nucleus of the ovum to form:
   A. Stigma
   B. Endosperm
   C. Anther
   D. Stamen

8. In a Datura flower, the stalk at the base of the flower is called the:
   A. Pedicel
   B. Corolla
   C. Sepals
   D. Thalamus

9. The male reproductive parts of a flower (the stamens) are collectively called:
   A. Androecium
   B. Filament
   C. Anther
   D. Gynoecium

10. The gynoecium in a flower is also referred to as the:
    A. Pistil
    B. Stigma
    C. Androecium
    D. Style

11. In a flowering plant, the functional megaspore grows into the:
    A. Endosperm
    B. Ovule
    C. Embryo sac
    D. Embryo

12. Which of the following is similar to autogamy but requires pollinators?
    A. Geitonogamy
    B. Cleistogamy
    C. Apogamy
    D. Xenogamy

13. The filiform apparatus in the embryo sac primarily functions to:
    A. Guide the entry of the pollen tube
    B. Recognise suitable pollen at the stigma
    C. Produce nectar
    D. Stimulate division of the generative cell

14. The nutritive tissue found outside the embryo sac is known as:
    A. Protoplasm
    B. Pericarp
    C. Ectoderm
    D. Perisperm

15. Identify the correct statement:
    A. Sporogenous tissue is haploid
    B. The hard outer layer of pollen is called intine
    C. Tapetum nourishes the developing pollen
    D. Microspores are produced by the endothecium

16. Which of these fruits is formed by parthenocarpy?
    A. Brinjal
    B. Apple
    C. Banana
    D. Jackfruit

17. The formation of seeds without fertilisation in flowering plants is known as:
    A. Budding
    B. Apomixis
    C. Sporulation
    D. Somatic hybridisation

18. In angiosperms, the functional megaspore develops into the:
    A. Endosperm
    B. Embryo
    C. Embryo sac
    D. Ovule

19. Rewards and attractants (like nectar) are essential for:
    A. Entomophily
    B. Cleistogamy
    C. Anemophily
    D. Hydrophily

20. A dioecious flowering plant (with separate male and female plants) prevents:
    A. Geitonogamy and xenogamy
    B. Autogamy and xenogamy
    C. Autogamy and geitonogamy
    D. Cleistogamy and xenogamy

Answer Key for MCQs

1 – A
2 – A
3 – C
4 – A
5 – A
6 – B
7 – B
8 – A
9 – A
10 – A
11 – C
12 – A
13 – A
14 – D
15 – C
16 – C
17 – B
18 – C
19 – A
20 – C

Short Practice Quiz (With Answers)

Try this mini-quiz to strengthen your knowledge.

Q1. Which structure in a pollen grain is responsible for forming the pollen tube?
a) Generative nucleus
b) Tube nucleus
c) Egg cell
d) Secondary nucleus

Answer: b) Tube nucleus

Q2. When both the male and female flowers grow on the same plant, it is described as:
a) Dioecious
b) Monoecious
c) Polygamous
d) Dichogamous

Answer: b) Monoecious

Q3. What is the ploidy level of the endosperm formed after double fertilisation?
a) Haploid (n)
b) Diploid (2n)
c) Triploid (3n)
d) Tetraploid (4n)

Answer: c) Triploid (3n)

Extra Tips for NEET Preparation

• Focus on sexual reproduction in flowering plants NEET questions that are concept-based.

• Practice labelling diagrams of the embryo sac, stamen, and pistil.

• Understand how parthenocarpy and apomixis are applied in horticulture.

• Revisit the concept of dioecious vs. monoecious to avoid confusion.

Related Topics You May Find Helpful

• Biomolecules

• Biotechnology Principles

• Important Questions on Sexual Reproduction in Flowering Plants