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प्रश्न
Briefly discuss any two methods by which plants avoid self-pollination.
उत्तर
The two methods to avoid self-pollination are:
- Dichogamy - In bisexual flowers, anthers and stigma mature at different times. Due to these maturation times, self-pollination is not possible.
- Prepotency - In numerous plants, pollen grains from one flower easily germinate on the stigma of another flower that is genetically distinct, as opposed to pollen grains from the same flower. This prevents self-pollination.
APPEARS IN
संबंधित प्रश्न
Mention two strategies evolved to prevent self-pollination in flowers.
Draw a diagram of a section of a megasporangium of an angiosperm and label funiculus, Micropyle, embryosac and nuclleus.
What is meant by pollination?
Differentiate between the following:
Self pollination and cross pollination.
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.
What is a flower? Draw a typical flower and label its different parts.
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 |
Which of the following floral adapation are adapted by hydrophilous flowers?
Mention any one example of the anemophilous flower.
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 | ______ |
