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प्रश्न
When an insect sits on the flower of a plant then some 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.
(a) 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?
(b) What is the name of tube B?
(c) What is C which moves down through the tube B?
(d) Name D and E.
(e) What is F?
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उत्तर
(a) A represents pollen grains. The process of transferring pollen grains from one flower to another flower of the similar plant by insects is known as cross pollination.
(b) B represents the pollen tube.
(c) C is the male gamete which moves down through the pollen tube (B).
(d) D is the female gamete (or egg). The structure E represents the ovule.
(e) F is the zygote.
APPEARS IN
संबंधित प्रश्न
Name and differentiate between the two modes of pollination in flowering plants.
State the name of the functional unit concerned with sexual reproduction.
Name the swollen lower part of the carpel.
Fill in the following blank with suitable word :
The term used to refer to the transfer of pollen from the stamen of one flower to the carpel of another flower of the same species is...........
Explain the term 'fertilisation'.
The part of a seed which grows and develops into root on germination is :
(a) cotyledon
(b) plumule
(c) follicle
(d) radicle
Put a tick mark (✓) against the correct alternative in the following statement
Reproductive whorls of a flower are:
What is a flower ? Draw a neat labelled diagram showing the L.S. of a typical flower.
Multiple choice question. Tick (✓) the correct choice:
Unisexual flowers are found in
- mulberry
- mustard
- pea
- sunflower
Fill in the blanks:
A carpel consists of ________ , ________ and ________.
In the figure, the parts marked A, B and C are sequentially:

(A) Plumule, Radicle and Cotyledon
(B) Radicle, Plumule and Cotyledon
(C) Plumule, Cotyledon and Radicle
(D) Radicle, Cotyledon and Plumule
Find the odd one out:
Calyx : Sepals : : Corolla : ________________
Accessory whorls : Calyx and corolla : : essential whorls : ______________
Distinguish between self-pollination and cross-pollination.
Draw a neat and labelled diagram.
Double fertilization in angiosperms
Explain the sexual reproduction process in plants with a diagram.
Double fertilization is exhibited by ______
Give any two examples of agents of pollination.
The figure below shows the concept of double fertilization. Complete the flow chart showing the progress at each step:

