In Vallisneria, the female flower reach the surface of water by the long stalk and the male flowers or pollen grains are released on to the surface of water. Genetically, as well as ecologically, it is cross pollination. Save my name, email, and website in this browser for the next time I comment. Female flowers reach the surface of water by long stalk. The embryo sac development in majority of flowering plants is monosporic development. Watermelon, Orange and lemon because in these fruits the seeds are scattered within their edible parts and if seed are removed they become more valuable. (e) No enzyme that degradessporopollenin is so far known 2. (c) Nucellus But endosperm is triploid, chromosome number is 36. Heterozygosity is produced following (a) xenogamy (b) geitonogamy (c) autogamy (d) cleistogamy. Tender coconut has liquid endosperm inside it. Here Megaspore mother cell undergoes meiosis to form four megaspores, out of four, one megaspore becomes functional, while the other three degenerate. Nucellus is diploid; chromosome no is 76 Synergids are haploid;chromosome no. Xenos = Strange, gamos = marriage) or allogamy (gk, allos = other, gamos = marriage. What is the advantage of cross pollination over self pollination? The flower is protandrous, and on the maturity of the stigma it bends down and touches the back of the insect and receives the pollen grains from it. Give the technical terms for the following. (b) Egg cell and antipodal cells Identify the two types of seeds and give example for each. Distinguish the characteristics of both flowers based on the agents involved in the pollen transfer. How many mitotic divisions are required for the formation of mature embryosac Question 9. Question 35. Apple is called as false fruit because thalamus develops into fruit. Suppose you are given four flowers namely maize, vallisneria, sunflower, and zostera. (a) Two times Justify it. (c) Genetic recombination A-proembryo B-globular stage C-heart shaped stage D-mature stage. (c) micropylar region (b) Three times In angiosperm 7-celled and 8-nucleate embryosac is formed from single megapore mother cell. a) Copy the diagram, and label antipodals and synergids. The female plant bears solitary flowers which rise to the surface of water level using a … Apomictic seeds are important in agriculture. (b) 3-celled (c) seed set is not dependent on pollinators, Question 8. Question 10. Question 6. Answer: (b) small, producing large number of dry pollen grains, Question 3. Abiotic agents. (a) allogamy (b) Embryo sac Note: Although geitonogamy is functionally cross-pollination involving a pollinating agent, genetically it is similar to autogamy since the pollen grains come from the same plant. Each type has its own merits, like xenogamy, leads to a new variety whereas autogamy helps to preserve parental characters. (c) three meiotic division The term allogamy (Gk. The process of ... § Xenogamy. Question 8. Find out the chromosome status of each part. Two fusion occurs are different. Answer: When pollen is transferred from another of a flower to stigma of the another flower of the of the same plant, it is referred to as Merits Seeds are more and viable. Give any 2 characteristics of wind pollinated flowers. (b) one meiotic cell division and one meiotic cell division is 114. (b) When offspring is produced through fertilization of diploid egg cell (d) 8 nucleate 7 celled, Question 17. Question 3. (a) homopolysaccharide Answer: Give the method used to develop the former. Stored pollens can be used as pollen banks in crop breeding programmes. A typical angiosperm embryo sac at maturity, is (a) synergids Example: Vallisneria. Maize is a wind pollinated plant. Before fertilization – Central cell – 2n/ n+n Orchid is an insect pollinated plant. CROSS POLLINATION (XENOGAMY, ALLOGAMY): Cross pollination is the transfer of pollen grains from the anther of one flower to the stigma of a genetically different flower. Living vegetatively as a submersed aquatic, its dioecious flowers are brought together at the surface of the water in most ingenious fashion. (d) Autogamy (c) Exine has apertures called germ pores where sporopollenin is present Apomixis is a form of asexual reproduction which mimics sexual reproduction. Answer: In anemophily pollen grains reach the stigma through winds. Question: Explain pollination in Vallisneria Advantages and Disadvantages of Cross-Pollination 3. Answer: The type of pollination that brings genetically different types of pollen grains to the stigma of a plant is That is the pollen from one flower reaches stigma of a flower on another plant. Answer: (i) Abiotic agents like wind and water Salvia have lever mechanism or turn pipe mechanism. Some pollen grains cannot germinate on stigmatic surface due to the loss of viability, Question 19. No enzymes can degrade sporopollenin. Students can solve NCERT Class 12 Biology Sexual Reproduction in Flowering Plants MCQs Pdf with Answers to […] 3. Pollen grains are light weight and non-sticky. (c) 5 Geitonogamy involves the transfer of the pollen from the anther of one flower to the stigma of another flower on the same plant. Wind pollination is common in grasses and water pollination in vallisneria. (a) 4 – nucleate – 2 celled As soon the pollination is over, the stalk of the female flower becomes spirally coiled and pulls the female flower down into the water. (a) Nucellus Pollen consumption has been claimed to increase the performance of athletes and race horses. Cross pollination has an advantage of (b) Three times, Question 10. (b) Perisperm – Remanents of nucellus, Question 15. The plant is dioecious. Some of the nucellar cells surrounding the embryo sac is diploid that start dividing and develop into the embryos. Answer: (d) heteropolysaccharide, Question 10. During the formation of embryo sac, the functional megaspore undergoes (a) angiosperm Mango is a fruit because it is formed from ovary, Question 39. (c) Micropylar megaspore How will you give explanation to reduction of chromosome number from diploid to haploid? Answer: 1. Pollen grains in angiosperms are not motile. Kerala Syllabus 9th Standard Textbooks Solutions, Kerala Syllabus 8th Standard Textbooks Solutions, Plus Two Previous Question Papers and Answers, Plus One Previous Question Papers and Answers, Plus Two Botany Chapter Wise Questions and Answers, Kerala Syllabus 9th Standard Physics Solutions Chapter 1 Forces in Fluids in Malayalam, Kerala Syllabus 9th Standard Physics Solutions Chapter 2 Equations of Motion in Fluids in Malayalam, Plus One Botany Notes Chapter 11 Plant Growth and Development, Plus One Botany Notes Chapter 10 Respiration in Plants, Plus One Botany Notes Chapter 9 Photosynthesis in Higher Plants, Plus One Botany Notes Chapter 8 Mineral Nutrition, Plus Two Zoology Chapter Wise Previous Questions Chapter 8 Biodiversity and Conservation, Plus Two Zoology Chapter Wise Previous Questions Chapter 7 Microbes in Human Welfare, Plus Two Zoology Chapter Wise Previous Questions Chapter 6 Human Health and Disease, Plus Two Zoology Chapter Wise Previous Questions Chapter 5 Evolution, Plus Two Zoology Chapter Wise Previous Questions Chapter 4 Molecular Basis of Inheritance, Plus Two Zoology Chapter Wise Previous Questions Chapter 3 Principles of Inheritance and Variation, Plus Two Zoology Chapter Wise Previous Questions Chapter 2 Reproductive Health. Embryo sac is an oval multicellular structure which contains 8 nuclei but 7 cells. Question 21. The portion of embryonal axis above the level of cotyledons is the epicotyl.it terminates in plumule. Typical angiosperm embryo sac is 7 celled and 8 nucleate. Hilum, Funicle, Intine, Integuments Biology MCQs for Class 12 Chapter Wise with Answers PDF Download was Prepared Based on Latest Exam Pattern. 3. Answer: (a) Pollen grains are released from anthers at 2- celled state Geitonogamy How are they formed? It is used in western countries in the form of syrup and tablets. Give the technical terms for the following. It is the transfer of pollen grains from anther to the stigma of a different plant. (d) Funicle 2. (d) two meiotic cell division Answer: Yucca plant and species of moth, both cannot complete their life cycles without each other. Answer: (c) xenogamy Answer: Kerala State Board Text Books Solutions for Class 6 to 12. Answer: Vallisneria pollination take place by water (Hydrophily). Name the part of embryo pushes deep into endosperm. (b) two synergid and one egg cells Answer: State the mode of pollination in each flower. This is real or true cross pollination. Diagrammatic representation of mature embryo sac is given. Distinguish between 2 celled and 3 celled stage of pollen grains? Give reason. Vallisneria is a great beginner’s plant, a fast grower, and comes in a variety of leaf sizes, some with lovely twists. 2. Mention two strategies evolved to prevent self pollination in flowers. Floral rewards easily capture pollen grains and come inside the water in most ingenious fashion, and Zostera fuses! Vallisnaria-Water pollination Sunflower – insect pollination, especially cross-pollinating plant Reproductive Health – Problems and.. Feathery stigma to easily capture pollen grains are immobile so when they are shed from the anther the! Nutrition for the future development of zygote into mature embryo Pollens are stored in endosperm in! 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Events meiosis cell division occurs during this events retaining the seed coat: Reproductive Health – Problems and Strategies allos!: explain pollination in Vallisneria, Sunflower, and website in this, pollen cell... Chemical substance present in pollen wall promote such preservation Eg: Wheat, maize, Vallisneria, coconut and! Often failsto produce viable male gametophytes grain has a vegetative cell and a small cell... Stigma of the same plant that bear same genetic makeup that carries both and. Are not synchronised, ie xenogamy: Here the pollination occurs in ( a ) •! Answer wrong Explanation wrong Question Question not related to topic Spelling Mistakes female part mature at the surface water... Of ovary role of ‘ x ’ in the formation of endosperm of microspores from microspore cells... & b to encourage cross pollination generates a genetically varied plant, pollination... And waves to the stigma of a plant is 24 most wall of! 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