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प्रश्न
Complete the following chart and rewrite.
| Sr.No. | Agencies | type of pollination |
| 1 | Water | .................... |
| 2 | ........................... | Entomophily |
| 3 | Bat | .................... |
| 4 | ....................... | Ornithophily |
(Or)
Explain outbreeding devices in angiospermic plants.
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उत्तर
1. Water Hydrophily
2. Insect Entomophily
3. Bat Chiropterophily
4. Birds Ornithophily
(Or)
1) Most of the Angiosperms produce bisexual flowers. Cross pollination is preferred by majority of flowering plants and they develop out breeding devices.
2) In many plants self pollination is avoided as stamens and carpels do not mature simultaneously. This
is called dichogamy.
3) In some plants, pollen grains are released much before stigma becomes receptive, this is protandry
e.g. Sunflower and in some plants, stigma becomes receptive first, this is protogyny e.g. Michelia.
4) The third device to avoid self pollination is genetic mechanism and it is called self-incompability or
self sterility, e.g. Orchids.
5) Pollen germination on the stigma of the same flower is inhibited. The fourth device is to produce
unisexual flowers. i.e. unisexuality.
6) In some plants like Castor, male and female flowers are produced on the same plant and such plants
are called monoecious. In dioecious plants like Papaya, male and female flowers are produced on
different plants. This condition prevents autogamy as well as geitonogamy while monoecious condition
prevents only autogamy.
APPEARS IN
संबंधित प्रश्न
Draw a diagram of a section of a megasporangium of an angiosperm and label funiculus, Micropyle, embryosac and nuclleus.
What is meant by pollination?
Can a unisexual flower be self pollinated?
Fill in the blanks with suitable words.
_______ is a water-pollinated flower.
Answer the following question.
Express the process of pollination in Vallisneria.
Describe the Advantages and Disadvantages of self-pollination to the Plant.
From among the situations given below, choose the one that prevents both autogamy and geitonogamy.
Pollination by water occurs in ______.
The flower which possesses both androecium and gynoecium is called perfect or ______.
What is ornithophily?
