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Q.1. The term used for transfer of pollen grains from anthers of one plant to stigma of a different plant which during pollination, brings genetically different types of pollen grains to stigma, is: (2021)
Explanation: Xenogamy – Transfer of pollen grains from anther to the stigma of a different plant. This is the only type of pollination which during pollination brings genetically different types of pollen grains to the stigma.
Q.2. A typical angiosperm embryo sac at maturity is: (2021)
(a) 7-nucleate and 7-celled
(b) 8-nucleate and 8-celled
(c) 8-nucleate and 7-celled
(d) 7-nucleate and 8-celled
Explanation: Thus, hilum represents the junction between ovule and funicle. Each ovule has one or two protective envelopes called integuments. Integuments encircle the nucellus except at the tip where a small opening called the micropyle is organised. Opposite the micropylar end, is the chalaza, representing the basal part of the ovule.
Q.3. In some members of which of the following pairs of families, pollen grains retain their viability for months after release? (2021)
(a) Poaceae; Solanaceae
(b) Rosaceae; Leguminosae
(c) Poaceae; Rosaceae
(d) Poaceae; Leguminosae
Explanation: In some cereals such as rice and wheat, pollen grains lose viability within 30 minutes of their release, and in some members of Rosaceae, Leguminoseae and Solanaceae, they maintain viability for months.
Q.4. Ray florets have: (2020)
(a) Hypogynous Ovary
(b) Half inferior Ovary
(c) Inferior Ovary
(d) Superior Ovary
Explanation: Ray florets have inferior ovary and the reason is that the other parts of the flower are attached above the level of ovary. Example of such an ovary is ray florets of sunflower.Flower showing Ray Floret
Q.5. The plant parts which consist of two generations one within the other: (2020)
(i) Pollen grains inside the anther
(ii) Germinated pollen grain with two male gametes
(iii) Seed inside the fruit
(iv) Embryo sac inside the ovule
(a) (iii) and (iv)
(b) (i) and (iv)
(c) (ii) only
(d) (i) only
(i) Pollen grain inside the anther (2n).
(iv) Embryosac inside ovule female gametophyte (2n).
Q.6. The body of the ovule is fused within the funicle at (2020)
Explanation: The body of the ovule fuses with the funicle in the region called the hilum. The funicle is a stalk through which the ovule is attached to the placenta.Q.7. The ovary is half inferior in: (2020)
Q.8. In water hyacinth and water lily, pollination takes place by: (2020)
(a) wind and water
(b) insects and water
(c) insects or wind
(d) water currents only
Explanation: In a majority of aquatic plants such as water hyacinth and water lily, the flowers emerge above the level of water and are pollinated by insects or wind as in most of the land plants. Their stem part which is above the thalamus is not in the water. The pollen grains are in the upper part of thalamus so pollination can't done by water. That's why it is done by insects and wind.
Q.9. Persistent nucellus in the seed is known as (2019)
Explanation: In some seeds, remains of nucellus persist.
This residual nucellus which persists in the seed is called perisperm
Examples: Black pepper, coffee, castor, cardamom, Nymphaea.
Q.10. What is the fate of the male gametes discharged in the synergid? (2019)
(a) One fuses with the egg and other fuses with central cell nuclei.
(b) One fuses with the egg, other(s) degenerates in the synergid.
(c) All fuse with the egg.
(d) One fuses with the egg, other(s) fuse(s) with synergid nucleus.
Q.11. Which one of the following statement regarding post-fertilisation development in flowering plants is incorrect? (2019)
(a) Ovules develops into embryo sac.
(b) Ovary develops into fruit.
(c) Zygote develops into embryo.
(d) Central cell develops into endosperm.
Explanation: Following are the post-fertilisation changes:
So, the correct answer is 'Ovules develop into embryo sac'
Q.12. Which is the most common type of embryo sac in angiosperms? (2019)
(a) Tetrasporic with one mitotic stage of divisions
(b) Monosporic with three sequential mitotic divisions
(c) Monosporic with two sequential mitotic divisions
(d) Bisporic with two sequential mitotic divisions
Q.13. What type of pollination takes place in Vallisneria? (2019)
(a) Pollination occurs in submerged condition by water.
(b) Flowers emerge above surface of water and pollination occurs by insects.
(c) Flowers emerge above water surface, pollen is carried by wind.
(d) Male flowers are carried by water currents to female flowers at surface of water.
Q.14. which one of the following, both autogamy and geitonogamy are prevented? (2019)
Explanation: Autogamy and geitonogamy are two forms of self-pollination. In autogamy, pollen falls on stigma of the same flower. While in geitonogamy pollens from a flower fall on the stigma of some other flower on the same plant. Papaya is a dioecious plant thus both autogamy and geitonogamy are prevented in it.
Q.15. Which of the following has proved helpful in preserving pollen as fossils? (2018)
(b) Cellulosic intine
(c) Oil content
Explanation: Exine of pollen grain is made up of highly resistant fatty substance called sporopollenin, which is not degraded by any enzyme. It is not affected by high temperature, strong acid or strong alkali. Because of the sporopollenin, pollen grains are well preserved as microfossils.
Q.16. Winged pollen grains are present in (2018)
Explanation: Each pollen grain of Pinus has two wing-like structures which enable it to float in the air, as an adaptation for dispersal by wind. Pollen grains of mustard, Cycas and mango are not winged.
Q.17. Double fertilisation is (2018)
(a) Fusion of two male gametes of a pollen tube with two different eggs
(b) Fusion of one male gamete with two polar nuclei
(c) Fusion of two male gametes with one egg
(d) Syngamy and triple fusion.
Q.18. Functional megaspore in an angiosperm develops into an (2017)
(b) Embryo sac
Explanation: In angiosperms, the functional megaspore is the first cell of female gametophyte. It enlarges and Undergoes three nuclear mitotic divisions to form embryo sac.
Q.19. Attractants and rewards are required for (2017)
Q.20. Flowers which have single ovule in the ovary and are packed into inflorescence are usually pollinated by (2017)
Explanation: Single ovule in the ovary and flowers racked into inflorescence are characteristics of wind-pollinated flowers.
Q.21. A dioecious flowering plant prevents both (2017)
(a) Autogamy and geitonogamy
(b) Geitonogamy and xenogamy
(c) Cleistogamy and xenogamy
(d) Autogamy and xenogamy.
Explanation: Dioecious plants are those plants in which male flowers and female flowers are borne on different plants. Therefore, they prevent both autogamy and geitonogamy.
Q.22. Double fertilisation is exhibited by (2017)
Explanation: Out of two sperms, when one sperm fertilizes with egg to form a diploid zygote. While the other sperm fuses with the two polar nuclei to develop triploid endosperm, the process is known as double fertilization. Double fertilization is the characteristic feature of angiosperm.
Q.23. In majority of angiosperms (2016)
(a) Egg has a filiform apparatus.
(b) There are numerous antipodal cells.
(c) Reduction division occurs in the megaspore mother cells.
(d) A small central cell is present in that embryo sac.
Q.24. Pollination in water hyacinth and water lily is brought about by the agency of (2016)
(b) Insects or wind
Q.25. The ovule of an angiosperm is technically equivalent to (2016)
(c) Megasporem other cell
Q.26. The coconut water from tender coconut represents (2016)
(a) Free nuclear proembryo
(b) Free nuclear endosperm
(d) Fleshy mesocarp
Explanation: The coconut water from tender coconut represents the free nuclear or liquid endosperm. During the development of nuclear type of endosperm, the primary endosperm mother cell divides by free nuclear divisions, and these divisions are not followed by cell wall formation. Thus, the free nuclei remain in the cytoplasm of the embryo sac.
Q.27. Which one of the following statements is not true? (2016)
(a) Pollen grains of many species cause severe allergies.
(b) Stored pollen in liquid nitrogen can be used in the crop breeding programmes.
(c) Tapetum helps in the dehiscence of anther.
(d) Exine of pollen grains is made up of sporopollenin.
So, the correct answer is 'Tapetum helps in the dehiscence of anther.'
Q.28. Seed formation without fertilisation in flowering plants involves the process of (2016)
(a) Somatic hybridisation
Explanation: Apomixis is a reproductive process which does not involve gametic fusion. In apomictic flowering plants there is no fertilisation and embryos develop simply by division of a cell of ovule.
Q.29. Which of the following statements is not correct? (2016)
(a) Pollen germination and pollen tube growth are regulated by chemical components of pollen interacting with those of the pistil.
(b) Some reptiles have also been reported as pollinators in some plant species.
(c) Pollen grains of many species can germinate on the stigma of a flower, but only one pollen tube of the same species grows into the style.
(d) Insects that consume pollen or nectar without bringing about pollination are called pollen/ nectar robbers.
Q.30. Proximal end of the filament of stamen is attached to the (2016)
(b) Thalamus or petal