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How plants reproduce By Ekaterina Zhdanova-Redman Spring is a wonderful time of a year. Flowers are everywhere. Blooming trees, bushes, and plants are beautiful. The air is filled with their sweet fragrances. Bees and butterflies are flying from one bright flower to another. Why do they do that? 1 You know, of course, that bees produce honey. They make it from nectar they gather from flowers. Nectar is a sweet and viscous liquid. It is located in plants' blossoms, leaves, and stems. Different living things use nectar as their food--bees, wasps, butterflies, moths, even some birds and mammals! But they are not the only ones who benefit from it. Nectar-eating insects and birds also help flowering plants reproduce. 2 You may have observed tiny yellow grains inside some flowers. This is called pollen and it is used by flowers to form seeds. Plants make the pollen in the saclike anthers of their flowers. The anthers are part of the stamen--the male part of reproduction. The female part is called the pistil, and it includes the stigma and the ovary. The stigma receives the pollen and leads it to the ovary--the egg-bearing part of the plant. The process of moving pollen from anthers to stigma is called pollination. 3 When pollen reaches the egg cell inside the ovary, it causes the cell to divide. Each cell then becomes a seed embryo and develops into the seed. This process is called fertilization. Because of fertilization, seeds have characteristics of both male and female cells. Some plants have both pistils and stamens on their flowers. They are perfect flowers. They can transfer pollen from their own anthers to their own stigmas. This process is called self-pollination. 4 It is necessary for self-pollinating flowers to prevent other plants' pollen from getting into their stigmas. This is why in some flowers the pollination occurs before the blossom opens. Some other flowers are so constructed that pollen from other blossoms simply can't enter them. Look at the flowers of beans, peas, or snapdragons. They grow a kind of a trap door for protection against other pollens. You may also notice that these flowers have no scent. Can you tell why? 5 6 But not all flowers are perfect. Some of them have only pistils and are considered female flowers. Others have only stamens, which makes them male flowers. These kinds of flowers are called cross-pollinating. They must depend on wind, insects, birds, or other means to carry their pollen from male flowers to female ones. This is why they have showy blossoms, a fragrant scent, and sweet nectar, all of which attract various insects and birds. They fly from flower to flower and transport sticky pollen on their feet and bodies. The type of reproduction you just learned about is called sexual. It requires female and male parts of plants to reproduce. Some plants have either male flowers or female flowers. Did you know that some plants have both male and female flowers on the same plant? Some plants even have all three kinds of flowers on the same plant--male, female, and perfect ones! The plants that have female, male, and perfect flowers on the same plant are called polygamous. 7 If some plants do not have flowers, seeds, or fruit, how do they reproduce? Some plants have special parts that produce tiny one-celled structures called spores. Each spore either alone or combined with another spore produces a new plant. The production of plants by means of spores that do not have male or female parts is called asexual (nonsexual) reproduction. 8 Another type of asexual reproduction is called vegetative. Instead of involving flowers and seeds, other parts of plants are used for reproduction. Potatoes, for example, will grow from pieces cut from them and planted. Other plants, like strawberries, send out trailing ground stew, which take root to produce new plants. Plants can reproduce from roots, slips, or leaves. In all those cases a new plant will be just like the old one. 9 Gardeners also have learned that a plant may grow from a slip attached to a stem of a different kind of plant. This process is called grafting. You may have seen an apple tree in which different branches grow different kinds of apples. A single apple tree once bore thirty different kinds of apples! 10 Copyright © 2015 edHelper Name _____________________________ How plants reproduce Date ___________________ 1. Insects flying from flower to flower gather _____. Honey Seeds Nectar Pollen 3. Pollen is used to form _____. Seeds Flowers Fruit Leaves 5. Pistils are a _____ part of reproduction. Male Female Neutral None of the above 7. Perfect flowers have _____. Both pistil and stamen Only pistils Only stamens None of the above 2. Nectar is located in _____. Flowers, leaves, and stems Roots Seeds Fruit 4. Stamens are a _____ part of reproduction. Male Female Neutral None of the above 6. The process of moving pollen is called _____. Cross-pollination Pollination Reproduction Self-pollination 8. The process of growing a new plant from a slip attached to a stem of a different plant is called _____.