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प्रश्न
What are the adaptations which are required in self-pollinated plants?
उत्तर
Adaptations required by cross-pollinated plants are:
(i) Unisexuality - The stamens and carpels are found in different flowers. The male and female flowers may be borne on the same or different plants.
(ii) Dichogamy - In bisexual flowers, stamens and carpels mature at different times. It is of two kinds:
(a) Protandry wherein stamens mature before carpels. E.g - jasmine
(b) Protogyny wherein carpels mature before stamens. E.g. - Rose
(iii) Heterostyly - Here the style is either longer or shorter, thereby preventing self-pollination.
(iv) Herkogamy - Stigma, and stamen mature at the same time, but some type of barrier prevents self-pollination. E.g. - In caryophyllaceous flower, the stigma projects beyond the stamens so that pollens cannot fall on it.
(v) Self-sterility - Pollen of one flower cannot fertilize the female gametes of the same flower.
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 of the item.
Give one word/term for the following:
Pollination of flowers by insects.
In bisexual flowers, maturation of gynoecium before androecium is known as ______.
Name the two types of pollination.
For which of the following attractants and rewards are required?
Male and female flowers are present on different plants (dioecious) to ensure xenogamy, in ______.
Heterostyly as a contrivance for cross-pollination is found in ______.
Which of the following plant contain unisexual flower?
During Hybridization process anther of the bisexual flower is removed before it dehisces is called ______.
In the dioecious aquatic plant shown, identify the characteristics of the male flowers that reach the female flowers for pollination:
| Size of the flower | Colour of flower | The characteristic feature of pollen grain | |
| A | small | brightly coloured | Lightweight and non-sticky |
| B | large | colourless | large and sticky |
| C | small | white | small, covered with mucilage |
| D | large | colourless | non-sticky |
