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How seeds are formed?   A flower exists to produce seed.  For that, two organs are essential.  Stamen produces pollen grains that later form the.

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Presentation on theme: "How seeds are formed?   A flower exists to produce seed.  For that, two organs are essential.  Stamen produces pollen grains that later form the."— Presentation transcript:

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2 How seeds are formed?

3   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. How seeds are formed?

4   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. How seeds are formed?(2)

5   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. How seeds are formed?(3)

6   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. How seeds are formed?(4)

7   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. How are seeds formed?(5)

8   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 nectaries in which a sweet liquid, called nectar, is secreted. How seeds are formed?(6)

9   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. How seeds are formed?(7)

10  How seeds are formed?(8&9) How seeds are formed?(8)  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. How seeds are formed?(9)  Such plants the term dioeciously is applied. The holly is an example.

11 Goodbye! Done by :Amanda Goh, Leong Hao Jie, Yap Jia Yi, Teng Zi Yi.


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