Sexual Reproduction In Flowering Plant Class 12th VVI MCQs Bihar Board

1. How many meiotic divisions are required to form 100 pollen grains?

• Correct Ans: (c) 25

• Explanation: One microspore mother cell undergoes a single meiotic division to produce 4 haploid pollen grains. Therefore, 100 pollen grains require $100 / 4 = 25$ meiotic divisions.

2. Double fertilization means

• Correct Ans: (c) Fusion of two polar nuclei and one male gamete (Note: This refers to triple fusion, which occurs alongside syngamy to complete the process of double fertilization).

• Explanation: It involves two fusion events inside the embryo sac: syngamy (fusion of a male gamete with the egg) and triple fusion (fusion of the second male gamete with the secondary nucleus).

3. Pollination by bats is called

• Correct Ans: (c) Chiropterophily

• Explanation: Chiropterophily is the specialized term for cross-pollination carried out by bats, usually occurring in large, night-blooming flowers.

4. Pollination by snails is called

• Correct Ans: (a) Malacophily

• Explanation: When pollination is mediated by snails or slugs moving over low-growing aquatic or terrestrial plants, it is termed malacophily.

5. Development of fruit without fertilization is called

• Correct Ans: (c) Parthenocarpy

• Explanation: Parthenocarpy is the process where an ovary develops into a fruit without undergoing fertilization, resulting in naturally seedless fruits like bananas.

6. Who discovered fertilization?

• Correct Ans: (b) Strasburger

• Explanation: Fertilization in plants (syngamy) was first discovered and described by the scientist Eduard Strasburger in the year 1884 in Monotropa.

7. Mature seeds in which endosperm persists are called

• Correct Ans: (a) Endospermic

• Explanation: These are also known as albuminous seeds, where the endosperm is not completely consumed during embryo development and remains to store food (e.g., maize, wheat).

8. The processes from zygote to embryo formation are called

• Correct Ans: (a) Embryogeny

• Explanation: Embryogeny encompasses the sequential stages of cell division, growth, and structural differentiation that transform a single-celled zygote into a mature embryo.

9. Perisperm is the remnant part of

• Correct Ans: (a) Nucellus

• Explanation: In certain seeds like black pepper and beet, the central nutritive tissue of the ovule (nucellus) persists as a thin, functional layer called the perisperm.

10. In which of the following aril is not found?

• Correct Ans: (c) Mango

• Explanation: The aril is an accessory fleshy seed-covering eaten in litchi and custard apple, whereas the edible portion of a mango is the mesocarp (fruit wall).

11. Which of the following fuses with a male gamete to form endosperm?

• Correct Ans: (d) Secondary nucleus

• Explanation: Just before triple fusion, the two haploid polar nuclei fuse to form a diploid secondary nucleus ($2n$), which then unites with a haploid male gamete ($n$) to create the triploid endosperm ($3n$).

12. Entomophily cross-pollination occurs by which of the following?

• Correct Ans: (b) Insects

• Explanation: Entomophily is the ecological relationship where insects (such as bees, moths, and butterflies) transfer pollen grains from anthers to stigmas.

13. Ornithophily cross-pollination occurs by

• Correct Ans: (c) Birds

• Explanation: Ornithophily refers to pollination carried out by birds (like hummingbirds and sunbirds) that visit brightly colored, tubular flowers for nectar.

14. What type of cross-pollination occurs in Vallisneria?

• Correct Ans: (a) Water-pollination

• Explanation: Vallisneria is a submerged aquatic plant where pollination takes place on the surface of the water (epi-hydrophily) as detached male flowers float toward the female flowers.

15. Anemophily pollination occurs by which of the following?

• Correct Ans: (a) Wind

• Explanation: Anemophily is wind-mediated pollination. Plants utilizing this mechanism produce lightweight, non-sticky pollen grains in massive quantities.

16. Wind-pollinated flowers are generally

• Correct Ans: (d) Both (b) and (c)

• Explanation: Since wind pollination doesn’t require animal attraction, the flowers evolve to be small, structurally simple, colorless, and completely devoid of scent or nectar.

17. Pollination by ants is called

• Correct Ans: (b) Myrmecophily

• Explanation: Myrmecophily is the specific botanical phenomenon where ants act as the active vectors for transferring pollen grains between flowers.

18. Generally, the endosperm in Capsella is

• Correct Ans: (c) Triploid

• Explanation: Capsella is a typical angiosperm, and like all angiosperms, its endosperm is formed via triple fusion, making its chromosomal status triploid ($3n$).

19. Which structure is not found in Angiosperms?

• Correct Ans: (a) Archegonium

• Explanation: The archegonium is the multicellular female reproductive organ typical of bryophytes, pteridophytes, and gymnosperms; it is completely absent in angiosperms.

20. Totipotency is

• Correct Ans: (c) Development of organism from cell in a medium

• Explanation: Cellular totipotency is the inherent genetic capacity of a single isolated plant cell to divide, differentiate, and regenerate into an entire, fully functional organism under sterile laboratory conditions.

21. Who proved that a cell is totipotent?

• Correct Ans: (d) Steward

• Explanation: F.C. Steward in 1958 structurally demonstrated totipotency by successfully regenerating complete carrot plants from isolated single cells of carrot phloem tissue.

22. A typical Angiosperm embryo sac is generally:

• Correct Ans: (d) Seven-cellular

• Explanation: The standard Polygonum-type embryo sac completes development by organizing its 8 nuclei into exactly 7 cells: 3 antipodals, 2 synergids, 1 egg cell, and 1 large central cell.

23. The structure found in the nucellus of an ovule which represents the last stage of sporophyte is called?

• Correct Ans: (a) Megaspore mother cell

• Explanation: The megaspore mother cell ($2n$) is a specialized diploid cell of the nucellus. It undergoes meiosis to transition from the sporophytic generation to the haploid gametophytic generation.

24. In porogamy, the pollen tube reaches the embryo sac through

• Correct Ans: (c) Micropyle

• Explanation: Porogamy is the most frequent path of fertilization where the elongating pollen tube enters the ovule directly through the apical opening called the micropyle.

25. During seed formation in an angiospermic plant, the secondary nucleus changes into

• Correct Ans: (b) Endospermic

• Explanation: Following triple fusion, the primary endosperm nucleus undergoes rapid mitotic divisions to form the nutritive endosperm tissue which sustains the embryo.

26. Which of the following is not present in the anther wall?

• Correct Ans: (d) Integument

• Explanation: The anther wall consists of four specific layers: epidermis, endothecium, middle layers, and tapetum. The integument is the protective covering found exclusively on ovules.

27. Which of the following is not present in the embryo sac?

• Correct Ans: (c) Megasporogenesis cell

• Explanation: A mature, organized embryo sac comprises an egg apparatus, polar nuclei, and antipodals. Megasporogenesis is the prior developmental process that creates the megaspore.

28. In nuclear endosperm, after the division of the primary endosperm nucleus

• Correct Ans: (b) Cell wall formation does not take place

• Explanation: In the free-nuclear type of endosperm development, the initial nuclear divisions are not followed by immediate cell-wall deposition, resulting in an open liquid containing many free nuclei.

29. What is fertilization?

• Correct Ans: (a) Fusion of egg and male nucleus

• Explanation: Fertilization (or syngamy) is defined as the physical fusion of a haploid male gametic nucleus with a haploid female egg cell to form a diploid zygote ($2n$).

30. Who discovered double fertilization?

• Correct Ans: (b) Nawaschin

• Explanation: Sergei Nawaschin in 1898 first discovered the unique phenomenon of double fertilization while conducting embryological studies on Lilium and Fritillaria.

31. Persistent calyx is found in which of the following?

• Correct Ans: (a) Brinjal

• Explanation: In plants like brinjal, tomato, and chili, the sepals (calyx) do not wither or drop off after fertilization; instead, they remain green and grow along with the developing fruit.

32. What is a zygote?

• Correct Ans: (b) Diploid

• Explanation: A zygote is always a diploid cell ($2n$) because it is the direct structural outcome of the fusion of two haploid ($n$) gametes during syngamy.

33. Polyembryony occurs maximum in

• Correct Ans: (a) Gymnosperms

• Explanation: While rare or restricted in angiosperms, the development of multiple embryos within a single seed (polyembryony) is a standard, highly frequent feature across gymnosperm taxa.

34. Who first discovered polyembryony?

• Correct Ans: (a) Antonie van Leeuwenhoek

• Explanation: Polyembryony was first historically recorded and described by Antonie van Leeuwenhoek in the year 1719 while examining the seeds of citrus fruits (oranges).

35. Generally, in a mature fertilized ovule, n, 2n, and 3n conditions are found respectively in

• Correct Ans: (d) Egg, nucellus, and endosperm

• Explanation: The gametic egg cell is haploid ($n$), the vegetative nucellus tissue is maternal and diploid ($2n$), and the post-fertilization endosperm tissue is triploid ($3n$).

36. After fertilization, the ovule changes into

• Correct Ans: (b) Seed

• Explanation: Post-fertilization triggers structural shifts where the protective integuments harden to turn the whole ovule into a seed, while the ovary wall becomes the fruit pericarp.

37. Parthenogenesis is generally found in

• Correct Ans: (a) Grapes

• Explanation: Natural parthenogenesis or seedless development occurs natively in specific horticultural varieties like grapes, yielding high-value commercial seedless fruits.

38. In an orthotropous ovule, the micropyle and chalaza are:

• Correct Ans: (c) In a straight line with the funicle

• Explanation: The orthotropous (or atropous) ovule is completely straight, meaning its micropyle, chalaza, and the attaching stalk (funicle) all lie along a single linear axis.

39. Meiotic division in an ovule occurs in

• Correct Ans: (b) Megaspore mother cell

• Explanation: The specialized, diploid megaspore mother cell isolated in the nucellus undergoes meiosis to produce a linear tetrad of four haploid megaspores.

40. The embryo sac originates from?

• Correct Ans: (d) Megaspore

• Explanation: In most angiosperms, three out of four megaspores degenerate, and the single remaining functional megaspore expands and divides mitotically to produce the embryo sac.

41. The innermost nutritive wall of the microsporangium is called?

• Correct Ans: (c) Tapetum

• Explanation: The tapetum forms the innermost physiologic boundary of the anther wall. It breaks down to feed and sustain the microspores as they develop into mature pollen.

42. Pollination in Semal occurs by?

• Correct Ans: (b) Birds

• Explanation: Semal (Bombax) produces large, red, thick-petaled blossoms rich in nectar, making it perfectly adapted for avian vectors (ornithophily).

43. Which of the following organs takes part in sexual reproduction in flowering plants?

• Correct Ans: (a) Flower

• Explanation: The flower is the specialized evolutionary reproductive shoot of angiosperms, containing the essential sporophylls (stamens and carpels) required for reproduction.

44. How many types of floral leaves are generally present in a typical flower?

• Correct Ans: (a) Four

• Explanation: A complete, typical flower organizes its modified leaves into four distinct structural whorls: calyx, corolla, androecium, and gynoecium.

45. Cultivation of flowers is called?

• Correct Ans: (a) Floriculture

• Explanation: Floriculture is a specialized branch of agriculture focusing entirely on the commercial cultivation, breeding, management, and marketing of ornamental and flowering plants.

46. The male reproductive structure of a flower is called?

• Correct Ans: (a) Androecium

• Explanation: The androecium represents the complete male reproductive whorl of a flower, with each individual structural component called a stamen.

47. The study of pollen and spores is called?

• Correct Ans: (a) Palynology

• Explanation: Palynology is the scientific domain tracking the external morphology, chemical composition, and fossil preservation of pollen grains and fungal/plant spores.

48. Which vitamin is particularly present in pollen grains?

• Correct Ans: (a) Vitamin B

• Explanation: Pollen grains are highly nutritious packages packed with proteins, carbohydrates, lipids, and are especially rich in the Vitamin B complex group.

49. Pollen grains of plants belonging to the sunflower family lose their viability after how many hours?

• Correct Ans: (a) Three hours

• Explanation: Unlike cereals whose pollen dies within 30 minutes, members of Asteraceae (sunflower family) retain pollen viability for a few hours (approximated here as 3 hours).

50. The father of Indian angiosperm embryology is

• Correct Ans: (d) P. Maheshwari

• Explanation: Professor Panchanan Maheshwari is globally renowned and revered as the Father of Indian Plant Embryology for his pioneering research in tissue culture and embryogenesis.

51. The seed germination in which cotyledons come above the ground is called:

• Correct Ans: (b) Epigeal

• Explanation: In epigeal germination, elongation of the hypocotyl actively pushes the seed cotyledons upward, exposing them above the surface of the soil (e.g., castor, bean).

52. Polyembryony is found in

• Correct Ans: (b) Citrus

• Explanation: Citrus plants (like lemons and oranges) frequently show adventive polyembryony, where additional maternal nucellar cells develop directly into extra embryos within a single seed.

53. Grafting is mostly impossible in monocots because they lack:

• Correct Ans: (a) Cambium

• Explanation: Successful grafting requires the vascular cambium layers of the stock and scion to fuse and heal. Monocot stems lack a lateral cambium layer entirely.

54. Double fertilization in gymnosperms was discovered by

• Correct Ans: (d) Nawaschin (Note: Double fertilization is a signature angiosperm trait; however, early observations of similar fusions in select gymnosperms like Ephedra are associated with historical researchers).

• Explanation: While double fertilization uniquely characterizes angiosperms, Sergei Nawaschin remains the premier global authority associated with detailing this dual fusion setup.

55. What is endosperm?

• Correct Ans: (c) Triploid

• Explanation: Angiosperm endosperm forms when a haploid male gamete nucleus fuses with the diploid secondary central nucleus, generating a triploid ($3n$) chromosomal tissue.

56. Nuclear endosperm occurs in which of the following?

• Correct Ans: (b) Coconut

• Explanation: The clear liquid interior of a green coconut is the classic textbook illustration of free-nuclear endosperm, containing millions of un-separated, floating nuclei.

57. Cellular endosperm occurs in

• Correct Ans: (a) Datura

• Explanation: In cellular endosperm development, every single nuclear division is accompanied by immediate layout of a cellulose cell wall, seen typically in Datura.

58. Endosperm originates from?

• Correct Ans: (b) Microspore (Note: This question contains a standard printing error in the source key. Biologically, endosperm originates from the Primary Endosperm Nucleus).

• Explanation: Based on the printed text option key, ‘(b)’ is selected; conceptually, it requires triple fusion between the polar nuclei and the microspore-derived male gamete.

59. Which of the following is diploid?

• Correct Ans: (c) Secondary nucleus (Note: The uploaded image shows a hand-drawn checkmark on option (a), which is scientifically incorrect since egg cells are haploid ($n$); the secondary nucleus is diploid ($2n$)).

• Explanation: The secondary nucleus is diploid ($2n$) because it is formed by the fusion of two separate haploid ($n$) polar nuclei before fertilization occurs.

60. Entry of pollen tube into the nucellus through the micropyle is called

• Correct Ans: (a) Porogamy (Note: The uploaded image shows a pencil mark on option (c) Mesogamy, which is incorrect for entry via the micropyle).

• Explanation: When the pollen tube follows the standard physiological pathway and passes through the micropylar opening of the ovule, the process is called porogamy.

61. A normal angiosperm embryo sac is

• Correct Ans: (d) Seven-cellular

• Explanation: The normal Polygonum-type structure finishes its developmental pathway containing exactly 7 individual cellular units housing 8 total nuclei.

62. The stalk of the ovule is called

• Correct Ans: (a) Funicle

• Explanation: The funicle is the distinct, cord-like cellular stalk that anchors the body of an individual ovule securely to the maternal placental wall of the ovary.

63. The place where the ovule attaches to the funicle is

• Correct Ans: (d) Hilum

• Explanation: The hilum represents the specific scar or point of structural fusion where the main body of the ovule detaches from its supporting stalk, the funicle.

64. An anatropous ovule is

• Correct Ans: (b) Inverted

• Explanation: An anatropous ovule curves fully backwards by 180° during its development, making it completely inverted with the micropyle facing down next to the funicle base.

65. Some flowers have natural barriers between the anther and stigma due to which pollination is difficult or does not occur, what are they called?

• Correct Ans: (c) Herkogamy

• Explanation: Herkogamy is a mechanical or structural barrier separating the anther and stigma in a bisexual flower to make self-pollination impossible (e.g., Calotropis).

66. The female reproductive organ of a flower is called?

• Correct Ans: (a) Gynoecium

• Explanation: The gynoecium forms the innermost, female reproductive whorl of a blossom. Its constituent structural modules are called pistils or carpels.

67. Cleistogamous flower occurs in which of the following?

• Correct Ans: (a) Commelina

• Explanation: Commelina produces underground cleistogamous flowers that remain permanently locked shut, forcing the plant to carry out absolute self-pollination.

68. Homogamy occurs in which of the following?

• Correct Ans: (a) Mirabilis Jalapa

• Explanation: Homogamy is a floral adaptation where both the male anthers and female stigma reach full physiological maturity at the exact same time, enabling self-pollination.

69. Which of the following is a herkogamous flower?

• Correct Ans: (b) Calotropis

• Explanation: Calotropis (Madar) exhibits extreme herkogamy where its pollen is locked up in specialized ‘pollinia’ structures, requiring specific insects to move them.

70. Flowers remain closed in

• Correct Ans: (b) Cleistogamy

• Explanation: Cleistogamy is a reproductive adaptation where specific flowers never open their petals, ensuring absolute genetic purity via forced self-pollination.

71. Which part of the plant contains one generation inside another generation?

• Correct Ans: (b) Seed

• Explanation: A seed holds three generations: the maternal seed coat ($2n$), the intermediate endosperm ($3n$), and the next embryonic sporophyte generation ($2n$).

72. A disadvantage of self-pollination is

• Correct Ans: (b) Dichogamy (Note: This question format is flawed in the original text key; biologically, continuous self-pollination causes inbreeding depression).

• Explanation: Based on the textbook key provided, option ‘(b)’ is noted, though outcrossing mechanisms like dichogamy naturally function to prevent self-pollination.

73. Development of carpel without fertilization is called

• Correct Ans: (a) Parthenocarpy

• Explanation: Parthenocarpy is the physiological phenomenon where unfertilized ovaries change into fruit, naturally creating structural seedlessness.

74. The egg apparatus contains

• Correct Ans: (d) Egg and synergid cells

• Explanation: Situated at the micropylar tip of the embryo sac, the egg apparatus is a three-celled complex made of one central egg cell and two flanking synergids.

75. The largest nucleus of a pollen grain is

• Correct Ans: (a) Tube nucleus

• Explanation: After the first asymmetric division of a microspore, a large vegetative cell with a massive, irregularly shaped vegetative/tube nucleus is formed.

76. After fertilization, the fruit is formed from which of the following?

• Correct Ans: (b) Ovary

• Explanation: The maternal ovary undergoes massive cellular expansion and hormonal changes post-fertilization to form the mature pericarp and body of a fruit.

77. The aril of which fruit is eaten?

• Correct Ans: (b) Litchi

• Explanation: The edible part of a litchi is a fleshy, juicy, white outgrowth originating directly from the funicle base, termed a succulent aril.

78. False fruit is formed from which of the following?

• Correct Ans: (a) Thalamus

• Explanation: A fruit is designated as false when parts of the flower other than the ovary—most commonly the receptacle or thalamus—swell to form the flesh.

79. Which of the following is an example of a false fruit?

• Correct Ans: (a) Apple

• Explanation: An apple is a false fruit (pome) because the core represents the true ovary, while the edible crisp flesh is formed by the enlargement of the thalamus.

80. True fruit develops from

• Correct Ans: (a) Ovary

• Explanation: A true fruit (eukaryotic fruit) is defined strictly as a post-fertilization structure developed solely from the wall and tissues of a mature ovary.

81. Pollination in Lotus occurs by

• Correct Ans: (c) Insects (Note: The original textbook printed key marks (a) Water, which is a common misconception. Since lotus flowers emerge high above the water line, they are pollinated by beetles and bees).

• Explanation: Lotus blossoms emerge completely out of the water, producing color and heat to attract insect pollinators, making entomophily the true mechanism.

82. Development of a haploid plant from pollen is called

• Correct Ans: (b) Somatic hybridization (Note: This is a typographical error in the source print key. The correct scientific process is Androgenesis/Anther Culture (c)).

• Explanation: While the printed option key marks ‘(b)’, generating whole haploid plants from immature pollen grains in a lab environment is called androgenesis.

83. When the number of embryos in an embryo sac is more than one, the condition is called

• Correct Ans: (d) Polyembryony

• Explanation: Polyembryony is defined as the concurrent presence or development of multiple independent embryos inside a single seed coat.

84. Ubisch bodies are secreted by

• Correct Ans: (a) Tapetum

• Explanation: The cellular tapetum layer synthesizes lipid-rich structures called Ubisch bodies, which supply sporopollenin to build the durable outer pollen wall (exine).

85. The hardest resistant organic substance known so far is

• Correct Ans: (c) Sporopollenin

• Explanation: Sporopollenin forms the outer wall of pollen grains. It is completely inert and impervious to any known biological enzymes, strong acids, or alkalis.

86. The female gametophyte in Angiosperms is called

• Correct Ans: (b) Embryo sac

• Explanation: The embryo sac is the female gametophyte because it represents the reduced, haploid phase that produces and houses the female gamete (egg cell).

87. The 7-celled and 8-nucleate structure in Angiosperms is

• Correct Ans: (a) Embryo sac

• Explanation: A mature female gametophyte (embryo sac) organizes its eight nuclei into seven discrete cells via cell wall placement.

88. Which part of the plant contains one generation inside another generation?

• Correct Ans: (b) Seed

• Explanation: A fertilized, protected seed holds the future sporophytic embryo embedded snugly within the supportive tissues of the parent generation.

89. Chiropterophily means

• Correct Ans: (a) Bat pollination

• Explanation: This is a pollination mechanism where bats act as active vectors, attracted by strong, fruity odors and abundant nectar production.

90. The most common type of ovule in Angiosperms is

• Correct Ans: (c) Anatropous

• Explanation: The anatropous (completely inverted) type of ovule layout is highly dominant across roughly 82% of all known angiospermic plant families.

91. Male gametes of Angiosperms are formed by the division of

• Correct Ans: (d) Generative cell

• Explanation: The smaller generative cell inside a pollen grain undergoes a single mitotic division to produce two non-motile male gametes.

92. In which of the given pairs of plant structures is the number of chromosomes haploid?

• Correct Ans: (b) Egg cell and antipodal cells

• Explanation: Both the egg cell and the antipodal cells are direct internal products of the haploid gametophytic generation, making them haploid ($n$).

93. The ovule in which the curvature brings the nucellus and embryo sac at right angles to the funicle is called

• Correct Ans: (a) Hemitropous

• Explanation: In a hemitropous (half-inverted) ovule, the body turns halfway, coming to lie horizontally at a strict $90^\circ$ angle relative to its supporting stalk.

94. Through which cell of the embryo sac does the pollen tube enter the embryo sac?

• Correct Ans: (d) Degenerating synergid cell

• Explanation: The pollen tube enters the embryo sac through the cytoplasm of one of the two synergids, which undergoes planned cell death (degeneration).

95. Which of the following represents an ovule where the embryo sac becomes horseshoe-shaped?

• Correct Ans: (c) Amphitropous

• Explanation: In an amphitropous ovule, the structural curvature is so intense that the embryo sac bends like a horseshoe.

96. What is the arrangement of nuclei in a typical embryo sac of dicotyledonous plants?

• Correct Ans: (b) 3 + 2 + 3

• Explanation: The 8 nuclei are distributed as 3 at the micropylar end (egg apparatus), 2 in the center (polar nuclei), and 3 at the chalazal end (antipodals).

97. A plant species has 8 chromosomes in its synergid cells. What will be the number of chromosomes in the cells of its aleurone layer?

• Correct Ans: (b) 24

• Explanation: Synergids are haploid ($n = 8$). The aleurone layer is part of the endosperm, which is triploid ($3n$). Therefore, $3 \times 8 = 24$.

98. Male gametes in angiosperms are formed by the division of?

• Correct Ans: (b) Generative cell

• Explanation: The generative cell undergoes a mitotic division inside either the pollen grain or the growing pollen tube to produce two functional male gametes.

99. Which of the following is surrounded by a callose wall?

• Correct Ans: (a) Microspore mother cell

• Explanation: Before undergoing meiosis, the microspore mother cell isolates itself from surrounding cells by synthesizing a thick, protective wall of callose.

100. What is a pollen chamber in gymnosperms?

• Correct Ans: (b) A cavity inside the ovule in which pollen grains are stored after pollination

• Explanation: In gymnosperms, the pollen chamber is a distinct structural pocket located at the apex of the nucellus designed to capture wind-blown pollen grains.

101. In which one of the following pairs of plant structures is the number of chromosomes haploid?

• Correct Ans: (b) Egg cell and antipodal cells

• Explanation: These structures form within the female gametophyte via regular mitotic divisions of a functional haploid megaspore, ensuring their haploid ($n$) status.

102. Seed coat develops from?

• Correct Ans: (a) Pericarp (Note: This contains a printing error in the source book key. Anatomically, seed coats develop from ovule integuments (c), while the pericarp is the fruit wall).

• Explanation: Following the original printed key selection ‘(a)’, note that technically the outer seed coat (testa) and inner coat (tegmen) differentiate from the integument layers.

103. The main characteristic of the ovary of Brassica campestris (Mustard) is

• Correct Ans: (a) Presence of replum

• Explanation: Mustard belongs to the Brassicaceae family, characterized by a single-chambered ovary that becomes two-chambered due to a false septum called a replum.

104. What is an antherozoid (pumunu)?

• Correct Ans: (c) Male gametophyte (Note: Biologically, an antherozoid is a flagellated male gamete (b); however, option (c) is marked in accordance with the source print key).

• Explanation: Following the provided choice ‘(c)’, an antherozoid represents the motile, flagellated male reproductive unit observed in primitive plant groups.

105. The haploid cell that forms the embryo sac by mitotic division is:

• Correct Ans: (d) Functional megaspore

• Explanation: The single functional megaspore ($n$) undergoes three successive free-nuclear mitotic divisions to organize into a 7-celled, 8-nucleate embryo sac.

106. The phenomenon of entry of pollen tube through the micropyle is called?

• Correct Ans: (a) Porogamy

• Explanation: Porogamy is the technical term used when the pollen tube follows the standard physiological route, entering via the micropyle.

107. Gymnosperm endosperm is

• Correct Ans: (a) Haploid

• Explanation: In gymnosperms, the endosperm forms prior to fertilization directly from the haploid megaspore, making it a purely haploid ($n$) maternal tissue.

108. The result of double fertilization is

• Correct Ans: (c) Endosperm

• Explanation: While syngamy produces the diploid zygote, the second fusion event (triple fusion) results in the formation of the nutritive endosperm tissue.

109. Hypanthodium inflorescence is found in

• Correct Ans: (a) Peepal

• Explanation: Plants of the genus Ficus (Peepal, Banyan, Fig) have a unique fleshy receptacle that forms a hollow cavity with an apical pore, known as a hypanthodium.

110. In which of the following plants seed is formed but not flower?

• Correct Ans: (d) Pine

• Explanation: Pine (Pinus) is a gymnosperm (meaning “naked seed”). These plants produce ovules openly on cones to form seeds but do not develop true flowers.

111. In angiosperms, the wall binding the tetrad of all four microspores is made of?

• Correct Ans: (b) Callose

• Explanation: After meiosis, the four immature microspores are held together in a tetrad cluster by a temporary wall made of callose carbohydrate.

112. In an anatropous ovule, the position of the micropyle is towards which side?

• Correct Ans: (b) Downward

• Explanation: Because an anatropous ovule is completely inverted by 180 degrees, the micropylar opening faces downward toward the base.

113. In angiospermic plants, the pollen tube releases male gametes into:

• Correct Ans: (d) Synergid cell

• Explanation: The pollen tube grows into the micropyle and directly ruptures inside the cytoplasm of one of the synergids to release its two male gametes.

114. Geocarpic fruit is

• Correct Ans: (b) Groundnut

• Explanation: In groundnut (Arachis hypogaea), after fertilization, the stalk elongates and pushes the developing ovary underground, where the fruit matures.

115. In flowering plants, archesporium gives rise to?

• Correct Ans: (d) Both wall and sporogenous cells

• Explanation: Archesporial cells undergo periclinal division to produce the primary parietal layer (forming the anther wall) and the primary sporogenous layer.

116. The male gametophyte of Angiosperms is

• Correct Ans: (c) Tri-cellular

• Explanation: A completely mature angiospermic male gametophyte consists of exactly three cells: one large vegetative tube cell and two small male gamete cells.

117. The presence of dicliny (unisexuality) within flowers prevents

• Correct Ans: (a) Autogamy but not geitonogamy

• Explanation: If a flower is unisexual, it cannot pollinate itself (preventing autogamy). However, pollen can still move to another flower on the same plant (geitonogamy).

118. What does the filiform apparatus formed at the entrance of the ovule do?

• Correct Ans: (a) Helps the pollen tube to enter a synergid cell

• Explanation: The filiform apparatus consists of finger-like projections in the synergids that secrete chemical signals to guide the pollen tube into the embryo sac.

119. Endosperm is completely consumed by the developing embryo in the seed of?

• Correct Ans: (c) Pea

• Explanation: Non-endospermic (exalbuminous) seeds like peas and beans completely absorb the endosperm during development, storing their food in thick cotyledons instead.

120. Transfer of pollen grains from the anther of a flower to the stigma of another flower on the same plant is called

• Correct Ans: (b) Geitonogamy

• Explanation: Geitonogamy is functionally cross-pollination because it requires a vector, but genetically it resembles self-pollination since both flowers share the same parent plant.

121. Wind-pollinated flowers are

• Correct Ans: (b) Small, producing dry pollen grains in large numbers

• Explanation: These flowers do not invest energy in color or nectar; instead, they produce millions of lightweight, non-sticky pollen grains easily carried by air currents.

122. In which of the following is pollination autogamous?

• Correct Ans: (c) Cleistogamy

• Explanation: Because cleistogamous flowers never open, their stigma can only receive pollen from the anthers within the same closed bud, ensuring absolute autogamy.

123. Wind pollination is commonly found in

• Correct Ans: (b) Grasses

• Explanation: Wind pollination (anemophily) is the highly dominant and characteristic method of reproduction across the grass family (Poaceae).

124. Filiform apparatus is a major characteristic of

• Correct Ans: (b) Synergid cell

• Explanation: The filiform apparatus is a specialized structural modification of the cell wall found exclusively at the micropylar tip of synergid cells.

125. Nucellar polyembryony is found in the species of which of the following?

• Correct Ans: (a) Gossypium (Note: While Citrus (d) is the classic example of nucellar polyembryony, option (a) is selected here based on the original printed key).

• Explanation: Following the provided option key ‘(a)’, nucellar polyembryony occurs when maternal sporophytic cells of the nucellus divide and form extra embryos.

126. In angiosperms, sometimes pollen grains affect the endosperm. This abnormality is called

• Correct Ans: (d) Xenia

• Explanation: Xenia is the direct phenotypic effect exercised by dominant alleles of a male pollen grain on tissues outside the embryo, most visibly on the endosperm color/shape.

127. Amphimixis is

• Correct Ans: (b) Fusion of sperm and egg

• Explanation: Amphimixis is the standard scientific term for normal sexual reproduction involving the legal fusion of male and female gametes to generate genetic variation.

128. The larger nucleus in a pollen grain is

• Correct Ans: (b) Generative nucleus (Note: Biologically, the vegetative/tube nucleus (c) is larger. Option (b) is provided here to match the book’s printed answer key).

• Explanation: Following the textbook choice ‘(b)’, note that during pollen development, the cell divides unequally to form a larger vegetative nucleus and a smaller generative nucleus.

129. Mesogamy is

• Correct Ans: (b) Entry of pollen tube through the integument

• Explanation: Mesogamy is the specific fertilization pathway where the elongating pollen tube breaches the ovule by boring directly through its protective side layers (integuments).

130. Raphe is

• Correct Ans: (b) Ridge formed by the funicle

• Explanation: In an inverted (anatropous) ovule, the portion of the funicle stalk that fuses along the side of the ovule body leaves a distinct, longitudinal structural ridge called the raphe.