Answer:
1. Answer : (c) By insect
Explanation: Lotus plants are cross-pollinated by beetles. Beetles are drawn towards the Lotus flowers by the characteristic odor of the nectar.
2. Answer : (b) Seed
Explanation: After fertilization occurs, each ovule develops into a seed. Each seed contains a tiny, undeveloped plant called an embryo. The ovary surrounding the ovules develops into a fruit that contains one or more seeds.
3. Answer : (a) Grape
Explanation: Parthenocarpy is seen in only plants. Parthenogenesis occurs in both plants and animals. Some of the examples where parthenocarpy includes pineapple, banana, guava, grapes, tomato, apple, papaya, etc.
4. Answer : (c) In a straight line with funiculus
Explanation: An orthotropous ovule has the micropyle and chalaza in a straight line of the funiculus. Such type of ovule is also known as straight or erect ovule. It is also known as anatropous ovule.
5. Answer : (b) Megaspore mother cell
Explanation: Meiotic division takes place in an ovule to form Megaspore mother cell. Meiotic cell division is a fertilization process in some plants it takes place in the ovule to form megasporangium.
6. Answer : (c) Development of tissues of all kinds from a cell in a medium
Explanation: The ability of a single cell to divide and produce all the differentiated cells in an organism, including extraembryonic tissues. Totipotent cells formed during sexual and asexual reproduction include spores and zygotes.
7. Answer : (d) seven-celled
Explanation: The embryo sac of angiosperms consists of seven cells. A typical angiosperm embryo at maturity is called 7 celled 8 nucleates. The cells are arranged in three sets. In the centre, there are two polar nuclei which are a part of the large central cell.
8.Answer : (b) Epigeal
Explanation: In many dicotyledons like beans, castor, and some monocotyledons, the cotyledon is pushed above the soil by rapid elongation of the hypocotyl and they function as photosynthetic organs till the establishment of the seedling. This kind of germination is known as epigeal germination.
9. Answer : (a) Cambium
Explanation: Monocots cannot be grafted as they lack cambium tissue. The dicot plants have the cambium tissue which is a meristematic tissue and is present in the vascular bundles of the plant. ... The lack of cambium in monocot plants makes it impractical to graft.
10. Answer : (c) 25
Explanation: One meiotic division in a pollen mother cell gives rise to 4 microspores, which develop into 4 pollen grains, therefore 25 meiotic divisions are required to produce 100 pollen grains.
11. Answer : (a) Malecophily
Explanation: The pollination in which snails and slugs help in doing pollination is called Malacophilous and the flower which got pollinated by the snails and slug are called malacophilous.
12. Answer : (a) Porogamy
Explanation: The pollen tube containing male gametes enters the ovule in majority of cases through micropyle by a process termed porogamy.
13. Answer : (a) Funicle
Explanation: Stalk of the ovule is called Funiculus or Funiculi. This is needed for the attachment of ovules to the placenta in the ovary.
14. Answer : (c) provides nourishment to the developing pollen grains
Explanation: The tapetum is a specialized layer of nutritive cells found within the anther, of flowering plants, where it is located between the sporangenous tissue and the anther wall. Tapetum is important for the nutrition and development of pollen grains, as well as a source of precursors for the pollen coat.
15. Answer : (a) Pollen grain
Explanation: Each ovule has an embryo sac. Which in turn has a single egg cell. Similarly, in a majority of angiosperms, each stamen consists of a bilobed anther, which in turn has two pollen sacs in lobe, consisting of pollen grains.
16. Answer : (a) Pentaploid
Explanation: Polyploidy is a condition that has more than two sets of chromosomes. If an angiosperm male plant is diploid and a female plant is tetraploid, the ploidy level of endosperm will be pentaploid because the female gametes undergoes meiosis and forms gametes (2n).
17. Answer :(a) geitonogamy
Explanation: The transfer of pollen grains from the anther of one flower to the stigma of another flower of the same plant is called geitonogamy. This transfer involves an agent of pollination. Genetically, it is similar to autogamy since the pollen grains come from the same plant.
18. Answer :(a) Grasses
Explanation: Grasses are commonly pollinated by the wind and are known as Anemophily. These are monocot plants. Tall grass-like plants known as cereal grasses produce kernels (called cereal grain) at the top of their stalks
19. Answer : (a) Synergids and antipodals
Explanation: Synergids and antipodals are the cells that are present in the embryo sac at the time of fertilization. Once the fertilization of the male gamete and the egg occurs and the zygote is formed. The synergids and antipodal cells degenerate after that and the ovary converts into a fruit.
20. Answer : (a) Ovary wall
Explanation: After fertilization, the mature, ripened ovary develops into a fruit. The ovary wall forms the covering of the fruit called fruit wall or pericarp.
21. Answer : (a) Rhizome
Explanation: The vegetative propagation through the underground stem or rhizome occurs in ginger.
22. Answer : (c) Castor
Explanation: castor is the example of a seed with endosperm, perisperm, and caruncle.
23. Answer : (a) Apple
Explanation: The false fruit includes seedless fruits. Some examples of false fruit are apple, pear, gourd, and cucumber that develop from the thalamus, cashew-nut develops from the peduncle, jackfruit and pineapple develop from the entire inflorescence. Some other examples are banana, strawberry, etc.
24. Answer : (c) 16
Explanation: Each pollen mother cell (PMC), by a meiotic division, gives rise to a group of four haploid microspores. Thus, 16 pollen mother cells undergo meiotic divisions to produce 64 pollen grains.
25. Answer : (c) free-nuclear endosperm
Explanation: In Cocos nucifera (coconut), the coconut water represents free-nuclear endosperm and the surrounding kernel represents the cellular endosperm.
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