NCERT NEET Biology English Medium Part-1 | Chapter 20 : Sexual Reproduction in Flowering Plants.

NCERT NEET Biology English Medium Part-1 | Chapter 20 : Sexual Reproduction in Flowering Plants.

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Question 1: Which of the following wall layers of microsporangium provides nourishment to the developing pollen grains?

1. Epidermis.
2. Endothecium.
3. Middle layers.
4. Tapetum.

Answer: d.

Question 2: The process of formation of microspores from a pollen mother cell (PMC) through meiosis is called?

1. Megasporogenesis.
2. Microsporogenesis.
3. Embryogenesis.
4. Parthenogenesis.

Answer: b.

Question 3: Sporopollenin, one of the most resistant organic materials known, is present in which layer of the pollen grain?

1. Intine.
2. Exine.
3. Vegetative cell wall.
4. Generative cell wall.

Answer: b.

Question 4: Which prominent apertures on the pollen exine lack sporopollenin?

1. Micropyle.
2. Germ pores.
3. Stomium.
4. Hilum.

Answer: b.

Question 5: In over 60 percent of angiosperms, pollen grains are shed at which of the following stages?

1. 2-celled stage.
2. 3-celled stage.
3. 4-celled stage.
4. Single-celled stage.

Answer: a.

Question 6: The inner wall of the pollen grain, the intine, is primarily composed of?

1. Cellulose and pectin.
2. Chitin and cutin.
3. Sporopollenin and cellulose.
4. Pectin and lignin.

Answer: a.

Question 7: Which of the following is a major cause of pollen allergy and bronchial afflictions in India, acting as a ubiquitous weed?

1. Amaranthus.
2. Parthenium.
3. Chenopodium.
4. Sorghum.

Answer: b.

Question 8: Pollen viability of cereals like rice and wheat is approximately?

1. 30 minutes.
2. 30 days.
3. 3 months.
4. 6 months.

Answer: a.

Question 9: Cryopreservation of pollen grains is done at what temperature using liquid nitrogen?

1. -120°C.
2. -196°C.
3. -80°C.
4. -273°C.

Answer: b.

Question 10: Multicarpellary, syncarpous pistil is characteristically found in?

1. Michelia.
2. Papaver.
3. Hibiscus.
4. Aloe.

Answer: b.

Question 11: The basal bulged part of the pistil is called?

1. Stigma.
2. Style.
3. Ovary.
4. Thalamus.

Answer: c.

Question 12: What is the equivalent structure of a megasporangium in seed plants?

1. Nucellus.
2. Ovule.
3. Embryo sac.
4. Carpels.

Answer: b.

Question 13: The point of attachment of the body of the ovule to the funicle is known as?

1. Chalaza.
2. Micropyle.
3. Hilum.
4. Raphe.

Answer: c.

Question 14: The mass of cells enclosed within the integuments of an ovule, bearing abundant reserve food materials, is the?

1. Endosperm.
2. Nucellus.
3. Embryo sac.
4. Synergids.

Answer: b.

Question 15: An ovule generally has a single embryo sac formed from a megaspore through?

1. Mitosis.
2. Meiosis.
3. Apomixis.
4. Parthenocarpy.

Answer: b.

Question 16: During megasporogenesis in a typical angiosperm, how many megaspores are normally functional?

1. One.
2. Two.
3. Three.
4. Four.

Answer: a.

Question 17: The method of embryo sac formation from a single megaspore is termed?

1. Monosporic development.
2. Bisporic development.
3. Tetrasporic development.
4. Apospory.

Answer: a.

Question 18: In a mature 8-nucleate embryo sac, how many nuclei are surrounded by cell walls?

1. Four.
2. Six.
3. Seven.
4. Eight.

Answer: b.

Question 19: The typical angiosperm embryo sac, at maturity, is?

1. 8-nucleate and 8-celled.
2. 7-nucleate and 8-celled.
3. 8-nucleate and 7-celled.
4. 7-nucleate and 7-celled.

Answer: c.

Question 20: The central cell in a mature embryo sac contains?

1. Single haploid nucleus.
2. Two polar nuclei.
3. Three antipodal nuclei.
4. One male gamete.

Answer: b.

Question 21: Which specific cellular thickenings at the micropylar tip of synergids help in guiding the pollen tube?

1. Obturator.
2. Filiform apparatus.
3. Placental tissue.
4. Suspensor.

Answer: b.

Question 22: Autogamy refers to pollination where pollen is transferred to the stigma of?

1. The same flower.
2. Another flower of the same plant.
3. Another flower of a different plant.
4. A different species altogether.

Answer: a.

Question 23: Flowers which do not open at all, ensuring complete autogamy, are called?

1. Chasmogamous.
2. Cleistogamous.
3. Geitonogamous.
4. Xenogamous.

Answer: b.

Question 24: Geitonogamy is functionally cross-pollination but genetically similar to?

1. Xenogamy.
2. Autogamy.
3. Hybridization.
4. Emasculation.

Answer: b.

Question 25: Which type of pollination reliably brings genetically different types of pollen grains to the stigma?

1. Cleistogamy.
2. Autogamy.
3. Geitonogamy.
4. Xenogamy.

Answer: d.

Question 26: Abiotic agents of pollination primarily include?

1. Wind and Water.
2. Insects and Birds.
3. Bats and Ants.
4. Wind and Insects.

Answer: a.

Question 27: Flowers pollinated by wind generally possess?

1. Large, colorful petals.
2. Nectar glands.
3. Single ovule in each ovary.
4. Heavy, sticky pollen.

Answer: c.

Question 28: Tassels in corn cob, which wave in the wind to trap pollen, are actually the?

1. Anthers.
2. Stigma and style.
3. Petals.
4. Bracts.

Answer: b.

Question 29: Pollination by water is quite rare in flowering plants and is largely restricted to about?

1. 10 genera, mostly dicots.
2. 30 genera, mostly monocots.
3. 50 genera, mostly dicots.
4. 100 genera, mostly monocots.

Answer: b.

Question 30: In which of the following marine seagrasses does pollination occur completely submerged under water?

1. Vallisneria.
2. Hydrilla.
3. Zostera.
4. Eichhornia.

Answer: c.

Question 31: Water hyacinth and water lily are pollinated mainly by?

1. Water currents.
2. Insects or wind.
3. Small fishes.
4. Raindrops.

Answer: b.

Question 32: In water-pollinated species, pollen grains are often protected from wetting by?

1. Sporopollenin only.
2. Mucilaginous covering.
3. Lignin deposition.
4. Waxy cuticle.

Answer: b.

Question 33: To sustain animal visits, flowers provide rewards predominantly in the form of?

1. Colors and scent.
2. Nectar and pollen grains.
3. Water and essential oils.
4. Large petals and sticky stigma.

Answer: b.

Question 34: The tallest flower of Amorphophallus is about?

1. 1 foot tall.
2. 3 feet tall.
3. 6 feet tall.
4. 10 feet tall.

Answer: c.

Question 35: A mutualistic relationship where neither species can complete its life cycle without the other is classically seen in?

1. Mango and wasps.
2. Yucca and moth.
3. Rose and bees.
4. Sunflower and beetles.

Answer: b.

Question 36: Continued self-pollination in plants typically results in?

1. Heterosis.
2. Inbreeding depression.
3. Polyploidy.
4. Enhanced vigor.

Answer: b.

Question 37: Dichogamy is an outbreeding device where?

1. Pollen and stigma are at different heights.
2. Pollen release and stigma receptivity are not synchronized.
3. Anthers and stigma are in different flowers on different plants.
4. The plant completely prevents pollen tube growth.

Answer: b.

Question 38: Self-incompatibility in flowering plants is fundamentally a?

1. Mechanical mechanism.
2. Genetic mechanism.
3. Nutritional deficiency.
4. Temperature-dependent mechanism.

Answer: b.

Question 39: In dioecious plants like papaya, which types of pollination are prevented?

1. Autogamy only.
2. Geitonogamy only.
3. Both autogamy and geitonogamy.
4. Xenogamy.

Answer: c.

Question 40: The ability of the pistil to recognize compatible pollen depends primarily on?

1. Mechanical fit.
2. Chemical dialogue between pollen and pistil.
3. Size of the pollen grains.
4. Wind speed.

Answer: b.

Question 41: If a pollen grain is compatible, the pollen tube typically travels through the style and enters the ovule via the?

1. Chalaza.
2. Integuments.
3. Micropyle.
4. Funicle.

Answer: c.

Question 42: What guides the entry of the pollen tube into one of the synergids?

1. Polar nuclei.
2. Filiform apparatus.
3. Egg cell.
4. Central cell.

Answer: b.

Question 43: In artificial hybridization, if the female parent bears bisexual flowers, removal of anthers before they dehisce is called?

1. Bagging.
2. Emasculation.
3. Dusting.
4. Tagging.

Answer: b.

Question 44: Syngamy refers to the fusion of a male gamete with the?

1. Synergid.
2. Egg cell.
3. Central cell.
4. Antipodal cell.

Answer: b.

Question 45: Triple fusion is a defining event in angiosperms that involves the fusion of a male gamete with?

1. Two synergids.
2. Two antipodal cells.
3. Two polar nuclei.
4. The egg and one synergid.

Answer: c.

Question 46: The primary endosperm nucleus (PEN) formed after triple fusion has a ploidy level of?

1. Haploid (n).
2. Diploid (2n).
3. Triploid (3n).
4. Tetraploid (4n).

Answer: c.

Question 47: The phenomenon involving two types of fusions (syngamy and triple fusion) in the embryo sac is termed?

1. Apomixis.
2. Double fertilization.
3. Parthenogenesis.
4. Polyembryony.

Answer: b.

Question 48: Following double fertilization, the central cell directly develops into the?

1. Zygote.
2. Primary endosperm cell (PEC).
3. Embryo.
4. Seed coat.

Answer: b.

Question 49: The primary function of the endosperm in angiosperms is to?

1. Protect the seed.
2. Provide nutrition to the developing embryo.
3. Facilitate seed dispersal.
4. Form the fruit wall.

Answer: b.

Question 50: In coconut, the surrounding white kernel represents the?

1. Free-nuclear endosperm.
2. Cellular endosperm.
3. Nucellar tissue.
4. Embryo.

Answer: b.

Question 51: The water from tender coconut is technically?

1. Liquid nucellus.
2. Free-nuclear endosperm.
3. Degenerated liquid embryo.
4. Cellular endosperm.

Answer: b.

Question 52: Seeds in which the endosperm is completely consumed by the developing embryo before seed maturation are called?

1. Albuminous seeds.
2. Non-albuminous seeds.
3. Perispermic seeds.
4. Apomictic seeds.

Answer: b.

Question 53: Typical examples of non-albuminous seeds include?

1. Wheat and maize.
2. Castor and coconut.
3. Pea and groundnut.
4. Barley and sunflower.

Answer: c.

Question 54: The early stages of embryo development in dicots and monocots are mostly similar. This process is called?

1. Embryogeny.
2. Endospermogenesis.
3. Syngamy.
4. Placentation.

Answer: a.

Question 55: A typical dicotyledonous embryo consists of an embryonal axis and?

1. One cotyledon.
2. Two cotyledons.
3. Scutellum.
4. Coleorhiza.

Answer: b.

Question 56: The portion of the embryonal axis above the level of cotyledons is known as?

1. Hypocotyl.
2. Epicotyl.
3. Radicle.
4. Root cap.

Answer: b.

Question 57: The single cotyledon situated towards one side of the embryonal axis in monocot embryos is specifically called?

1. Epiblast.
2. Scutellum.
3. Coleoptile.
4. Hypocotyl.

Answer: b.

Question 58: In monocot embryos, the shoot apex and leaf primordia are enclosed in a hollow foliar structure termed?

1. Coleorhiza.
2. Scutellum.
3. Coleoptile.
4. Epiblast.

Answer: c.

Question 59: The un-differentiated sheath enclosing the radicle and root cap in monocots is the?

1. Coleoptile.
2. Coleorhiza.
3. Perisperm.
4. Integument.

Answer: b.

Question 60: Remnants of the nucellus that are persistent in seeds like black pepper and beet are known as?

1. Endosperm.
2. Pericarp.
3. Perisperm.
4. Aril.

Answer: c.

Question 61: The tough protective seed coats are formed from the ovule's?

1. Integuments.
2. Nucellus.
3. Funicle.
4. Synergids.

Answer: a.

Question 62: The small pore left in the seed coat that facilitates oxygen and water entry during germination is the?

1. Hilum.
2. Micropyle.
3. Chalaza.
4. Stomium.

Answer: b.

Question 63: As a seed matures, its water content is reduced drastically, commonly reaching?

1. 1-5 percent of its mass.
2. 10-15 percent of its mass.
3. 30-40 percent of its mass.
4. 50-60 percent of its mass.

Answer: b.

Question 64: When the embryo enters a state of metabolic inactivity to survive unfavorable conditions, the state is termed?

1. Vernalization.
2. Stratification.
3. Dormancy.
4. Quiescence.

Answer: c.

Question 65: True fruits develop strictly from the?

1. Thalamus.
2. Ovary.
3. Calyx.
4. Entire inflorescence.

Answer: b.

Question 66: The wall of the ovary develops into the fruit wall, which is technically called the?

1. Testa.
2. Tegmen.
3. Pericarp.
4. Endocarp.

Answer: c.

Question 67: Fruits in which parts other than the ovary, such as the thalamus, contribute to fruit formation are termed?

1. True fruits.
2. False fruits.
3. Parthenocarpic fruits.
4. Aggregate fruits.

Answer: b.

Question 68: Which of the following is a classic example of a false fruit?

1. Mango.
2. Apple.
3. Tomato.
4. Grape.

Answer: b.

Question 69: Fruits that develop without fertilization of the ovary are called?

1. Pseudocarps.
2. True fruits.
3. Parthenocarpic fruits.
4. Apomictic fruits.

Answer: c.

Question 70: Parthenocarpy can often be artificially induced through the application of?

1. Herbicides.
2. Growth hormones.
3. Insecticides.
4. Liquid nitrogen.

Answer: b.

Question 71: The oldest known viable seed, derived from Arctic Tundra and germinating after approximately 10,000 years, belongs to?

1. Phoenix dactylifera.
2. Lupinus arcticus.
3. Strobilanthes kunthiana.
4. Ginkgo biloba.

Answer: b.

Question 72: A viable seed of a date palm, discovered during the archaeological excavation at King Herod’s palace, was estimated to be how old?

1. 200 years.
2. 1000 years.
3. 2000 years.
4. 10,000 years.

Answer: c.

Question 73: The phenomenon of producing seeds without fertilization is known as?

1. Amphimixis.
2. Apomixis.
3. Parthenocarpy.
4. Polyembryony.

Answer: b.

Question 74: Genetically, apomixis is considered a form of?

1. Sexual reproduction.
2. Asexual reproduction mimicking sexual reproduction.
3. Vegetative propagation exclusively.
4. Tissue culture.

Answer: b.

Question 75: The presence of more than one embryo in a seed is termed?

1. Apomixis.
2. Placentation.
3. Polyembryony.
4. Parthenogenesis.

Answer: c.

Question 76: In many Citrus and Mango varieties, polyembryony occurs when which cells start dividing and protrude into the embryo sac?

1. Synergids.
2. Nucellar cells.
3. Integument cells.
4. Antipodal cells.

Answer: b.

Question 77: Why is apomixis considered highly valuable for the hybrid seed industry?

1. It requires constant artificial cross-pollination.
2. It prevents the segregation of hybrid traits in progeny.
3. It lowers the seed viability over years.
4. It decreases the overall crop yield.

Answer: b.

Question 78: During microsporogenesis, the microspore tetrad cells separate and develop into pollen grains as the anther?

1. Hydrates.
2. Dehydrates.
3. Absorbs nutrients.
4. Synthesizes sporopollenin.

Answer: b.

Question 79: The larger cell in a mature 2-celled pollen grain, which has abundant food reserve and a large irregular nucleus, is the?

1. Generative cell.
2. Vegetative cell.
3. Stalk cell.
4. Body cell.

Answer: b.

Question 80: Which cell floats in the cytoplasm of the vegetative cell and is responsible for forming the two male gametes?

1. Synergid.
2. Generative cell.
3. Tapetal cell.
4. Microspore mother cell.

Answer: b.

Question 81: Anemophily is the term used for pollination facilitated by?

1. Insects.
2. Birds.
3. Water.
4. Wind.

Answer: d.

Question 82: Entomophily refers to pollination carried out primarily by?

1. Wind.
2. Water.
3. Insects.
4. Bats.

Answer: c.

Question 83: In Vallisneria, the female flower reaches the surface of the water by?

1. Floating detached from the plant.
2. A long coiled stalk.
3. Secretion of mucilage.
4. Producing large air bubbles.

Answer: b.

Question 84: Plants like Zostera release their pollen grains which are characteristically?

1. Small and spherical.
2. Long, ribbon-like.
3. Spiny and heavy.
4. Winged and dry.

Answer: b.

Question 85: The foul odor emitted by some flowers is an adaptation to attract which specific pollinators?

1. Bees and butterflies.
2. Hummingbirds.
3. Flies and beetles.
4. Moths and wasps.

Answer: c.

Question 86: The process of removing anthers from a bisexual flower bud is crucial in artificial hybridization to prevent?

1. Xenogamy.
2. Unwanted self-pollination.
3. Bird damage.
4. Premature flower opening.

Answer: b.

Question 87: In artificial hybridization, bagging of emasculated flowers is done using bags typically made of?

1. Polythene.
2. Butter paper.
3. Muslin cloth.
4. Silk.

Answer: b.

Question 88: The ploidy level of the nucellus, megaspore mother cell, and functional megaspore is respectively?

1. n, 2n, n.
2. 2n, 2n, n.
3. 2n, n, n.
4. 2n, 2n, 2n.

Answer: b.

Question 89: In typical angiosperms, what happens to the antipodals and synergids post-fertilization?

1. They form the endosperm.
2. They differentiate into seed coats.
3. They degenerate.
4. They divide rapidly to form fruit tissue.

Answer: c.

Question 90: Albuminous seeds retain endosperm because?

1. It is not completely consumed during embryo development.
2. The embryo lacks cotyledons.
3. The seed coat is extremely thin.
4. It is converted into perisperm.

Answer: a.

Question 91: The structural adaptation in some seeds that helps in dispersal by animals or wind, formed as a fleshy or hairy outgrowth, is known generally as an?

1. Aril or coma.
2. Endosperm.
3. Epiblast.
4. Obturator.

Answer: a.

Question 92: The portion of the embryonal axis that terminates in the radicle and root cap is the?

1. Epicotyl.
2. Hypocotyl.
3. Scutellum.
4. Plumule.

Answer: b.

Question 93: In the grass family, the cotyledon is specialized into a structure designed to absorb nutrients from the endosperm, called the?

1. Coleoptile.
2. Coleorhiza.
3. Scutellum.
4. Epiblast.

Answer: c.

Question 94: A tiny, undeveloped fruit produced without fertilization, notably used to describe varieties like seedless bananas, is an example of?

1. True parthenocarpy.
2. Induced apomixis.
3. Polyembryony.
4. Vegetative propagation.

Answer: a.

Question 95: Apomictic embryos in Citrus are identical clones of the parent plant because they are derived from?

1. Fertilized egg cells.
2. Haploid synergids.
3. Diploid maternal somatic cells like nucellus.
4. Fused polar nuclei.

Answer: c.

Question 96: What is the main ecological benefit of wind-dispersed pollen being produced in massive quantities?

1. To provide food for insects.
2. To compensate for the high loss of pollen during transit.
3. To increase the weight of the stigma.
4. To accelerate the drying of the stamen.

Answer: b.

Question 97: Flowers offering safe places to lay eggs as a floral reward are observed in species like?

1. Amorphophallus.
2. Rose.
3. Jasmine.
4. Marigold.

Answer: a.

Question 98: Pollen-pistil interaction is considered a dynamic process primarily involving?

1. Random chance collisions.
2. Wind direction and moisture.
3. Pollen recognition followed by promotion or inhibition.
4. Temperature variations strictly.

Answer: c.

Question 99: If a pollen tube enters the ovule through the chalazal end, the phenomenon is called?

1. Porogamy.
2. Mesogamy.
3. Chalazogamy.
4. Syngamy.

Answer: c.

Question 100: The formation of seeds is critical for angiosperms because seeds?

1. Offer dependable means of reproduction independent of water.
2. Produce harmful toxins to deter herbivores.
3. Prevent mutations from occurring in the embryo.
4. Replace the function of the root system.

Answer: a.

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