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प्रश्न
List the different types of pollination depending upon the source of pollen gain.
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उत्तर
Pollination is the process of transfer of pollen grains from anther to stigma.
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Depending on the source of pollen grains, pollination can be divided as follows:
- Autogamy - It is the transfer of pollen grains from anther to stigma of the same flower. Autogamy requires the anther and the stigma to lie close. It also requires synchrony in the pollen release and stigma receptivity. Plants like Viola and Oxalis produce two kinds of flowers: chasmogamous flowers (with exposed anther and stigma) and cleistogamous flowers (plants that do not open at all and in which only autogamy occurs).
- Geitonogamy - It is the transfer of pollen grains from the anther of one flower to the stigma of another flower in the same plant. Genetically, it is similar to autogamy, but it requires pollinating agents.
- Xenogamy - It is the transfer of pollen grains from the anther to the stigma of a different plant. Pollination causes genetically different pollen types to be brought to a plant.
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संबंधित प्रश्न
Differentiate between the following:
Self pollination and cross pollination.
Exine and intine are the parts of
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Give an account of any two biotic agents for pollination along with their adaptations.
Autogamy can occur in a chasmogamous flower if ______.
Pollination occurs in ______.
Consider the following statements depicting adaptation of flowers to carryout successful pollination.
- Stigma is long, sticky and unwettable.
- Sepals, petals or perianth (if present) have waxy coating.
- Stamens with long filament and versatile anthers.
- Tubular corolla is seen.
- Flowers are noctumal.
Which of the above statements clearly depict hydrophily?
Which of the following floral adapation are adapted by hydrophilous flowers?
Complete the following table:
| Sr. | Type of pollination | Agent | Kind of flower | Examples |
| (i) | ______ | Wind | ______ | Maize |
| (ii) | Chiropterophily | ______ | Dull colour, with strong fragrance, abundant nectar | Adansonia |
| (iii) | Entamophily | Insects | ______ | Rose/Jasmine |
| (iv) | Ornithophily | ______ | Brightly coloured, large and showy. They secrete profuse, dilute n ectar | ______ |
