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How seeds are formed?

How seeds are formed?. How seeds are formed?. A flower exists to produce seed. For that, two organs are essential. S tamen produces pollen grains that later form the male cells, or sperms. It has stalk, or filament, at the tip of which is the pollen sac, or anther. .

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How seeds are formed?

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  1. How seeds are formed?

  2. How seeds are formed? • A flower exists to produce seed. • For that, two organs are essential. • Stamen produces pollen grains that later form the male cells, or sperms. • It has stalk, or filament, at the tip of which is the pollen sac, or anther.

  3. How seeds are formed?(2) • Pistils are usually in the centre of the flower, is the female organ. • It has three fairly distinct parts: The ovary, which contains one or more immature seeds, called ovules; above the ovary, a slender style, or tube; at the tip of the style, the stigma, on which the pollen is deposited.

  4. How seeds are formed?(3) • Stamen and pistil are called essential organs because they are necessary if there is to be seed. • 2 other organs ; sepals and petals are not involved in sexual reproduction.

  5. How seeds are formed?(4) • Some flowers do not have sepals and petals. We call them accessory organs. A flower that has all four organs is a complete flower. • The sepals are the lowest of the four organs.

  6. How are seeds formed?(5) • They look like leaves and their main function is to protect the bud until it has developed into a flower. • The sepals collectively are called the calyx.

  7. How seeds are formed?(6) • Above and inside the calyx are the petals, known collectively as the corolla. In many flowers they are coloured. • Petals of many flowers have glands nectariesin which a sweet liquid, called nectar, is secreted.

  8. How seeds are formed?(7) • Colours of the nectar, and the odours of essential oils produced by the petals of many flowers attract insects, hummingbirds, people, and other creatures, which, with wind and gravity. • The reproductive organs are formed in separate flowers on the same plant.

  9. How seeds are formed?(8&9) How seeds are formed?(8) How seeds are formed?(9) Such plants the term dioeciously is applied. The holly is an example. • Such plants are said to be monoecism. The watermelon, cucumber, and other members of the gourd family are examples. • Individual plants of some species have one-sexed flowers that is, flowers on a plant may have only stamens, and the flowers of another plant of the species may have only pistils.

  10. Thank you for paying attention. Goodbye!

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