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प्रश्न
Can cross-pollination occur in cleistogamous flowers? Give reasons for your answer.
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उत्तर
Cross-pollination cannot occur in cleistogamous flowers. Cleistogamous flowers do not open at all. In these flowers, the anthers and stigma are close together; when the anthers dehisce in the flower buds, pollen grains touch the stigma, resulting in pollination. As a result, these flowers are always self-pollinated since they remain closed, and cross pollen cannot land on the stigma. Cleistogamous flowers can pollinate and set seeds without pollinators.
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संबंधित प्रश्न
As a senior biology student you have been asked to demonstrate to the students of secondary level in your school, the procedure(s) that shall ensure cross-pollination in a hermaphrodite flower. List the different steps that you would suggest and provide reasons for each one of them.
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A flower of tomato plant following the process of sexual reproduction produces 240 viable seeds.
Answer the following questions giving reasons :
(a) What is the minimum number of pollen grains that must have been involved in the pollination of its pistil?
(b) What would have been the minimum number of ovules present in the ovary?
(c) How many megaspore mother cells were involved?
(d) What is the minimum number of microspore mother cells involved in the above case?
(e) How many male gametes were involved in this case?
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Add a note on pollination mechanism in Salvia.
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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State the name of the chief pollinating agent against the corresponding plant by choosing from those given in brackets.
Dahlia_______ .
Fill in the blanks with suitable words.
_______ is a water-pollinated flower.
When maturation time of reproductive parts in a flower is different.
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State four features of flowers pollinated by insects.
Give four adaptations shown by flowers pollinated by wind.
Name the two types of pollination.
Write different modes of pollination in detail with suitable examples.
What are the adaptations which are required in self-pollinated plants?
At which stage pollen grains are shed from the anther in Angiosperms?
Give an account of any two biotic agents for pollination along with their adaptations.
Which of the following plant contain unisexual flower?
In which one of the following pollination is autogamous?
From among the situations given below, choose the one that prevents both autogamy and geitonogamy.
What is hypohydrophily?
Give any four floral adaptations for chiropterophily.
When and why does a plant breeder employ the emasculation technique?
Which one of the following flower is hypohydrophilous?
In sea grass, pollens are long, ribbon like and without exine exhibiting ______ pollination.
Hydrophily (Hypo) is characterized by which of the following conditions?
Which of the following is classified as biotic agents of pollination?
Geitonogamy is characterized by which of the following?
