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प्रश्न
Autogamy can occur in a chasmogamous flower if ______.
पर्याय
Pollen matures before maturity of ovule
Ovules mature before maturity of pollen
Both pollen and ovules mature simultaneously
Both anther and stigma are of equal lengths.
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उत्तर
Autogamy can occur in a chasmogamous flower if both pollen and ovules mature simultaneously.
Explanation:
Autogamy in chasmogamous flowers occurs when pollen and ovules mature at the same time, allowing pollen to fertilize ovules within the same flower. Without simultaneous maturity, self-pollination is unlikely in open flowers like chasmogamous ones.
APPEARS IN
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.
Explain the post-pollination events leading to seed production in angiosperms.
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?
A flower of tomato plant following the process of sexual reproduction produces 200 viable seeds.
Answer the following questions giving reasons :
(a) What would have been the minimum number of ovules present in pre-pollinated pistil ?
(b) How many microscope mother cells would minimally be required to produce requisite number of pollen grains ?
(c) How many pollen grains must have minimally pollinated the carple ?
(d) How many male gametes would have used to produce these 200 viable seeds ?
(e) How many megaspore mother cells were required in this process ?
Make a list of any three outbreeding devices that flowering plants have developed and explain how they help to encourage cross-pollination.
Can cross-pollination occur in cleistogamous flowers? Give reasons for your answer.
What is self-incompatibility?
Why does self-pollination not lead to seed formation in self-incompatible species?
Add a note on pollination mechanism in Salvia.
The transfer of pollen grains from the anther to the stigma of the same or of another flower of the same kind is known as ______.
Describe the structure of its microsporangium.
Fill in the blanks:
The two kinds of pollination are __________ and __________.
Select and write the most appropriate answer from the given alternatives for the following subquestion:
A versatile anther is an adaptation for _______ type of pollination.
Which one of the following is one of the characteristics of self-pollinated flowers?
Give one word/term for the following:
Pollination of flowers by birds.
Mention any two contrivances in flowers which favour cross-pollination.
Give four adaptations shown by flowers pollinated by wind.
The question has four options. Choose the correct answer:
Pollination by insect is known as
Give an account of any two biotic agents for pollination along with their adaptations.
Autogamy can occur in a chasmogamous flower if ______.
Wind pollination is common in ______.
Both chasmogamous and cleistogamous flowers are present in ______.
In some plants anther and stigma mature at the same time this condition is called ______.
The flower which possesses both androecium and gynoecium is called perfect or ______.
Which type of pollination does the figure indicate?
Advantage of cleistogamy is:
Match the Column I with Column II.
| Column I | Column II |
| A. Pea | (i) Xenogamy |
| B. Jawar | (ii) Epihydrophily |
| C. Maize | (iii) Anemophily |
| D. Vallis | (iv) Bisexual |
| E. Cannabis | (v) Geitonogamy |
Mention any one example of the hydrophilous flower.
Name the following:
Aquatic plants which are anemophilous.
Briefly discuss any two methods by which plants avoid self-pollination.
