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प्रश्न
Make a list of any three outbreeding devices that flowering plants have developed and explain how they help to encourage cross-pollination.
List any three outbreeding devices that flowering plants have developed for cross-pollination and explain how they help to encourage cross-pollination.
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उत्तर
- Dichogamy: Flowers are unisexual, so self-pollination is not possible. The plants may be monoecious, bearing both male and female flowers (e.g. maize), or dioecious, bearing male and female flowers on separate plants (e.g. mulberry, papaya).
- Prepotency: Pollen grains of another flower germinate more rapidly on the stigma than pollen grains of the same flower. Examples of this include apples and grapes.
- Self-sterility (Self-incompatibility): Pollen grains of a flower do not germinate on the stigma of the same flower because of the presence of similar self-sterile genes. Examples of this include tobacco, potatoes, and crucifers.
APPEARS IN
संबंधित प्रश्न
List the different types of pollination depending upon the source of pollen gain.
Name the part of the flower which the tassels of the corn- cob represent.
What are chasmogamous flowers?
Name two characteristics of flowers in which pollination occur by wind.
Fill in the blanks:
The two kinds of pollination are __________ and __________.
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.
Mention any two contrivances in flowers which favour cross-pollination.
Type of interaction where an individual sacrifices its own welfare (life) for the benefit of another animal of its own species is ______.
Write different modes of pollination in detail with suitable examples.
What are the adaptations which are required in self-pollinated plants?
Give an account of any two biotic agents for pollination along with their adaptations.
Cleistogamous flowers are ______.
Plants with ovaries having only one or a few ovules are generally pollinated by ______.
Which of the following plant contain unisexual flower?
What is ornithophily?
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?
Mention any one example of the hydrophilous flower.
Bird pollinated flowers are usually ______.
Which of the following is classified as biotic agents of pollination?
Which plant is an example of ornithophily?
