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NCERT Based MCQ with Explanation:
1. What part of a flower develops into a fruit after fertilization?
(A) Ovule
(B) Ovary
(C) Petal
(D) Thalamus
Explanation: The ovary develops into the fruit, while ovules develop into seeds. This is part of post-fertilization events.
2. Which layer of the anther provides nourishment to the developing pollen grains?
(A) Epidermis
(B) Endothecium
(C) Tapetum
(D) Middle layer
Explanation: Tapetum is the innermost layer of the anther wall and nourishes the developing pollen grains with nutrients.
3. What is the ploidy of the primary endosperm nucleus formed during double fertilization?
(A) Haploid
(B) Diploid
(C) Triploid
(D) Tetraploid
Explanation: The primary endosperm nucleus is formed by the fusion of two polar nuclei (haploid) and one male gamete (haploid), resulting in a triploid structure.
4. What are cleistogamous flowers?
(A) Flowers that remain open to allow cross-pollination
(B) Flowers that remain closed, ensuring self-pollination
(C) Flowers pollinated by water
(D) Flowers pollinated by animals
Explanation: Cleistogamous flowers never open, so the anthers and stigma are enclosed together, ensuring self-pollination.
5. Which of the following is NOT a function of the pollen tube?
(A) Transport of male gametes
(B) Growth through the style to reach the ovule
(C) Nourishing the zygote
(D) Entry through the micropyle
Explanation: The pollen tube transports male gametes and grows toward the ovule, but it does not nourish the zygote.
6. What is the function of the filiform apparatus in a synergid?
(A) Guides the pollen tube into the ovule
(B) Facilitates double fertilization
(C) Stores food for the embryo
(D) Nourishes the antipodals
Explanation: The filiform apparatus, found at the micropylar tip of synergids, plays a crucial role in directing the pollen tube towards the embryo sac.
7. Which part of a flower serves as a landing platform for pollen grains?
(A) Ovule
(B) Style
(C) Stigma
(D) Anther
Explanation: The stigma is the receptive part of the pistil where pollen grains land during pollination.
8. In a mature embryo sac, how many cells are present?
(A) 7 cells
(B) 8 cells
(C) 4 cells
(D) 5 cells
Explanation: A mature embryo sac contains 7 cells with 8 nuclei, including 1 egg cell, 2 synergids, 3 antipodals, and 1 central cell.
9. What is the primary function of sporopollenin in pollen grains?
(A) Transport nutrients
(B) Resist environmental stresses
(C) Facilitate fertilization
(D) Store water
Explanation: Sporopollenin is a highly resistant material in the exine of pollen grains, protecting them from high temperatures, acids, and enzymes.
10. Double fertilization results in the formation of which two products?
(A) Zygote and antipodals
(B) Zygote and endosperm
(C) Pollen grain and ovule
(D) Embryo sac and fruit
Explanation: In double fertilization, one male gamete fuses with the egg cell to form the zygote, and the other fuses with the polar nuclei to form the triploid endosperm.
11. Which type of pollination involves pollen transfer between flowers of the same plant?
(A) Autogamy
(B) Geitonogamy
(C) Xenogamy
(D) Cleistogamy
Explanation: Geitonogamy involves the transfer of pollen to a flower on the same plant, making it genetically similar to autogamy.
12. In which plant does water serve as the pollination agent?
(A) Rose
(B) Vallisneria
(C) Mango
(D) Hibiscus
Explanation: Vallisneria uses water currents for pollination. The male flowers float on water and reach the female flowers.
13. What is the function of the synergids during fertilization?
(A) They produce the endosperm
(B) They attract and guide the pollen tube
(C) They form the embryo
(D) They nourish the egg cell
Explanation: Synergids produce signals to attract the pollen tube and guide it to the egg apparatus for fertilization.
14. Which term describes the production of seeds without fertilization?
(A) Parthenocarpy
(B) Apomixis
(C) Polyembryony
(D) Vivipary
Explanation: Apomixis is the formation of seeds without fertilization, mimicking sexual reproduction but involving no gamete fusion.
15. What prevents inbreeding in plants with hermaphrodite flowers?
(A) Self-incompatibility
(B) Parthenocarpy
(C) Tapetum degeneration
(D) Seed dormancy
Explanation: Self-incompatibility is a genetic mechanism that prevents self-pollen from fertilizing the ovule, reducing inbreeding depression.
16. What is the ploidy of the functional megaspore in angiosperms?
(A) Haploid
(B) Diploid
(C) Triploid
(D) Tetraploid
Explanation: The functional megaspore is formed after meiosis and is haploid.
17. What is the significance of the tapetum being bi-nucleate?
(A) Provides more energy for pollen formation
(B) Facilitates cell division in anthers
(C) Forms a protective layer around pollen
(D) Increases sporopollenin production
Explanation: The bi-nucleate nature of tapetal cells ensures sufficient nutrient and enzyme production for pollen development.
18. Which component of the embryo sac participates in triple fusion?
(A) Egg cell
(B) Synergid cells
(C) Polar nuclei
(D) Antipodals
Explanation: The two polar nuclei fuse with one male gamete to form the triploid primary endosperm nucleus.
19. Which tissue connects the ovule to the placenta?
(A) Funicle
(B) Hilum
(C) Micropyle
(D) Integument
Explanation: The funicle is the stalk-like structure that attaches the ovule to the placenta.
20. What structure in grass embryos corresponds to the cotyledon?
(A) Plumule
(B) Scutellum
(C) Coleoptile
(D) Radicle
Explanation: In grass embryos, the scutellum functions as the cotyledon and is specialized for nutrient absorption.
21. What is the role of the germ pore in pollen grains?
(A) Nutrient exchange
(B) Pollen tube emergence
(C) Prevent water loss
(D) Releasing sporopollenin
22. What type of embryo development occurs in most angiosperms?
(A) Bisporic
(B) Monosporic
(C) Tetrasporic
(D) Multisporic
23. In apomixis, how does the embryo develop?
(A) From a fertilized zygote
(B) From an unfertilized egg cell
(C) From endosperm cells
(D) From synergids
24. Which plant part is described as anatropous?
(A) Ovule
(B) Anther
(C) Embryo sac
(D) Pollen tube
25. What is the function of antipodal cells in the embryo sac?
(A) Fertilization of the egg cell
(B) Nutrition to the embryo sac
(C) Formation of endosperm
(D) Guiding pollen tubes
26. What does a mature pollen grain contain at the time of shedding?
(A) Two vegetative cells
(B) Two male gametes and one vegetative cell
(C) One vegetative cell and one generative cell
(D) Three synergids
27. In which part of the ovule does megasporogenesis occur?
(A) Chalaza
(B) Funicle
(C) Nucellus
(D) Integuments
28. Which type of endosperm is found in coconut water?
(A) Cellular
(B) Helobial
(C) Free-nuclear
(D) Parenchymatous
29. What is the main function of the exine layer of pollen grains?
(A) Providing nutrition
(B) Preventing dehydration and damage
(C) Enabling germination
(D) Supporting the ovary
30. Which among the following plants produces cleistogamous flowers?
(A) Hibiscus
(B) Rose
(C) Viola
(D) Mango
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