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प्रश्न
Give some examples of different modes of fertilisation in nature?
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उत्तर
There are two modes of fertilisation, i.e., external fertilisation as seen in case of fishes and frogs, and internal fertilisation that happens in humans, dogs, etc.
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संबंधित प्रश्न
How does fertilisation occur in flowers? Name the parts of the flower that develop into (i) seed, and (ii) fruit after fertilisation.
Name the parts A, B and C shown in the following diagram and state one function of each.
Name the part made up of the stigma, style and ovary.
What are the reproductive organs in a flower?
Where is the male gamete formed in flowering plants?
Where is the female gamete formed in flowering plants?
Draw a neat sketch of the carpel of a flower. Mark in it stigma, style and ovary.
Describe the process of fertilisation in a flower with the help of labelled diagrams.
One of the following occurs in the reproductive system of flowering plants as well as that of humans. This is :
(a) vas deferens
(b) anther
(c) ovary
(d) style
| When an insect sits on the flower of a plant then somene particles A present in the top of little stalks in the flower attach to its body hair. When this insect now sits on the flower of another similar plant, then particles A attached to the hair of insect are put on the top of a flask-shaped organ at the centre of flower. The particle A grows a long tube B from the top of flask-shaped organ through which C moves down and reaches the bottom part of flask-shaped organ. Here C fuses with the nucleus of D contained in structure E. The fusion of C and D forms a new cell F which grows and develops into a seed of the plant. |
- What are particles A? What is the process of transferring A from one flower to another flower of similar plant by the insect known as?
- What is the name of tube B?
- What is C which moves down through the tube B?
- Name D and E.
- What is F?
In a bisexual flower, inspite of the young stamens being removed artificially, the flower produces fruit. Explain.
Draw a diagram of the longitudinal section of a flower exhibiting germination of pollen on stigma and label (i) ovary, (ii) male germ-cell, (iii) female germ-cell and (iv) ovule on it.
What is cleistogamy? Write one advantage and one disadvantage of it, to the plant.
Distinguish between self-pollination and cross-pollination.
The male reproductive part of a flower is ______.
Antipodal cells are present towards the ______ in an anatropous ovule.
The 3-celled egg apparatus at the micropylar end comprises of ______
Pineapple fruit develops from ______.
The ovaries of different flowers may contain ______.
Sketch and label the essential and accessory whorls of flower.
