... maize, barley, castor, sunflower). persistent nucellus in seed. Genetically geitonogamy is equivalent to self pollination. Answer and Explanation: 30. The ovule is vascularised. So the fully developed normal type of female gametophyte or embryo sac is 8-nucleated and 7-celled structure. It is of two types haploid and diploid parthenogenesis. 21. It is (a) orthotropous (b) anatropous © campylotropous (d) amphitropous. The genesis of the plant embryo is the process that produces an embryo from the plant of an egg fertilized by asymmetric cell division and differentiation of undifferentiated cells into tissues and organs. Table S1. 7D, E ). Wrong! A flower is emasculated and auxins are applied to the stigma of the flower, it forms a parthenocarpic fruit. (b) persistent nuccllus (c) peripheral part of endosperm (d) disintegrated secondary nucleus. In marginal placentation ovary is unilocular and the placenta develops along the junction of the two margins of the carpel, called the ventral suture. 113. Which one of the following is surrounded by a callose wall? Parthenocarpic fruits are seedless. Leeuwenhoek © F.C. Difference between Perisperm and Endosperm. The role of double fertilization in angiosperms is to produce (a) cotyledons (b) endocarp © endosperm (d) integuments. (a): Normal type of sexual reproduction having two regular features, i.e., meiosis and fertilization, is called amphimixis. Cellular totipotency was demonstrated by (a) Theodore Schwann (b) A.V. Clusters of raphides (from nucellus cells that have been crushed during the expansion of the endosperm) are present between the endosperm and the persistent layer of nucellus tissue . Nucellar embryo is (a) amphimictic haploid (b) amphimictic diploid © apomictic haploid (d) apomictic diploid. Answer and Explanation: 1. ©: For the formation of 100 zygotes, 100 male gametes and 100 female gametes (eggs) are required. The successive type of cytokinesis is common in monocots. It inolves karyokinesis followed by cytokinesis. are naked. The role of double fertilization in angiosperms is to produce (a) cotyledons (b) endocarp © endosperm (d) hormones. The archesporium gives rise to parietal cells and primary sporogenous tissue. It provides the nutrition to the developing embryo. What type of placentation is seen in sweet pea? Answer and Explanation: 2. This phenomenon first observed by Nawaschin, 1898 in Lilium and FriUllaria. When pollen of a flower is transferred to the stigma of another flower of the same plant, the pollination is referred to as (a) autogamy (b) geitonogamy © xenogamy (d) allogamy. Total number of meiotic division required for forming 100 zygotes/100 grains of wheat is (a) 100 (b) 75 © 125 (d) 50. (a) amphitropous (b) circinotropous © atropous (d) antropous. Here both meiotic I and II nuclear divisions are followed by wall formation and it leads to isobilateral tetrad. Answer and Explanation: 19. (d): In an orchid Ophrys speculum, there is most interesting and unique mechanism of pollination. Vallisneria. Answer and Explanation: 7. (i) Nucellus : It is the massive parenchymatous region of the ovule. One nucleus from each group conies in centre to form 2 polar nuclei. All these features are shown by coconut flower. In a cereal grain the single cotyledon of embryo is represented by (a) coleoptile (b) coleorhiza © scutellum (d) prophyll Answer: © scutellum 62. Nucellus in a diploid tissue so the nucellar embryo is apomictic diploid. Eichhornia. Answer and Explanation: 9. (d): Anther consists of microsporangia or pollen sacs. Plants belonging to same species have mostly every character common and will be able to reproduce freely with each other to produce new generations. The contents of pollen tube are discharged in the synergid and the pollen tube does not grow beyond it in the embryo sac. Number of nuclei in mature stage may have different patterns but most common pattern in eight-nucleate one with one egg nucleus in egg cell, two synergids at micropylar end, three antipodal cells at opposite pole and two polar nuclei in middle of sac. 35. Answer: (d) one male gamete with egg and other with secondary nucleus. (b): Antipodal cells and egg cell are haploid structures as they are after meiosis while the others nucellus, megaspore mother cell and primary endosperm nucleus are diploid structures. The primary sporogenous cell gives rise to microspore mother cells or pollen mother cells. 28. 40. The appearance and odour of Ophrys is similar to female wasp and are mistake by male wasps and they land on Ophrys flowers to perform act of pseudo-copulation and thus pollin takes place. (a) egg cell (b) persistant synergid © degenerated synergids (d) central cell. In polygonum type of embryosac, which is found in 70% of angiosperms, only the chalazal megaspore remains functional while the other three degenerate. 200 pollen grains will be formed by 50 microspore mother cell while 200 eggs will be formed by 200 megaspore mother cell so 250/500. It is contrary to the situation seen in incomplete dominance. (a): A diploid female plant and a tetraploid male plant are crossed. 12. Answer and Explanation: 46. Answer and Explanation: 32. The organisms, which possess both the reproductive organs are bisexual. 56. The ovule consists of a large nucellus surrounded by a single integument. 15. Here pollination occurs by a wasp called Culpa aurea. 45. Entry of pollen tube through micropyle is (a) chalazogamy (b) mesogamy © porogamy (d) pseudogamy Answer and Explanation: 16. Answer: (b) downward 50. Answer and Explanation: 22. Apomixis may be defined as, ‘abnormal kind of sexual reproduction in which egg or other cells associated with egg (synergids, antipodals, etc.) Answer: (a) amphitropous 57. 61. The polygonum type of embryo sac is eight nucleate and seven celled. b. Answer and Explanation: 45. How plant seeds originated remains unresolved, in part due to disconnects between fossil intermediates and developmental genetics in extant species. b) Dioecious organisms are seen only in plants ... Q21. Answer and Explanation: 63. 31. (a): Arrangement of ovules inside the ovary on placenta is called placentation. Fritillaria type. 8 Type of pollination seen in Vallisneria is 1)Entamophily 2) Epihydrophily 3) Hypohydrophily 4) Anemophily 9 Emasculation is perfomed during hybridization to 1) Avoid undesirable pollination 2) Support undesirable pollination 3) Facilitate controlled artificial pollination 4) Both 1 and 3 It appears as a reddish papery structure. 3. make tea when they came west. These undergo periclinal (transverse) division to form an outer primary parietal cell and inner sporogenous cell. The anthesis is a phenomenon, which refers to (a) development of anthers (b) opening of flower bud © stigma receptors (d) all of these. The nucleus of megaspore undergoes divisions and give rise to embryo sac or female gametophyte, which is called megagametogenesis. Answer and Explanation: 53. (d): Development of an organism from female gamete/egg without involving fertilization is parthenogenesis and when fruit is developed by this technique it is called parthenocarpy. (ii) Bisporic type — Here embryo sac develops from 2 megaspore nuclei out of 4 nuclei formed after reduction division of MMC. Inside the anther, primary sporogenous cell gives rise to microspore mother cells or pollen mother cells (MMC or PMC). Whereas all the other three are found inside ovule, (nucellus, micropyle and embryo sac). This plant-insect relationship is useful only to plant. Answer and Explanation: 48. Answer and Explanation: 55. Female gametophyte of angiosperms is represented by (a) ovule (b) megaspore mother cell © embryo sac (d) nucellus. Funiculus, chalaza, embryo sac and micropyle lie in the same vertical axis. Answer and Explanation: 34. Autogamy is the transfer of pollen grains from anther to stigma of the same flower. These two acts together are known as double fertilization. 25. (d): Nucellar embryo is apomictic diploid. Whereas intine made of pectocellulose cc-, wrs the entire stirfucv pollen grains. 58. (a) and (b) seedlings with two cotyledons. It is also called xenogamy. Remaining 3 nuclei at micropylar end constitute egg apparatus and remaining 3 nuclei at chalazal end constitute 3 antipodal cells or antipodals. ... except for the sterility expected from a 3n rice plant. And beet, remnants of nucellus 3 + 2 + 3 arrangement mango etc because pollens found! 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