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प्रश्न
Answer the following question.
What is pollination? Explain the different types of pollination.
What is meant by pollination?
उत्तर १
The transfer of pollen grains from anther to stigma is known as pollination.
It is of two types:-
- Self-pollination:-It is the transfer of pollen grains from the anther to the stigma of the same flower or another flower on the same plant.
- Cross-pollination:-It is the transfer of pollen grains from the anther to the stigma of the flower present on two different plants.
उत्तर २
Pollination is the process of transfer of pollen grains from the anther to the stigma of the flower.
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संबंधित प्रश्न
A student identified the various parts of an embryo of a gram seed and listed them as given below :
(I) Testa
(II) Plumule
(III) Radicle
(IV) Cotyledon
(V) Tegmen
Out of these the actual parts of the embryo are :
(A) I, II, III
(B) II, III, IV
(C) III, IV, V
(D) II, IV, V
"The chromosomal number of the sexually producing parents and their offspring is the same." Justify this statement.
The anther contains ______.
Name the male part of the flower.
Where are the pollen grains produced?
What is the function of a flower?
What are the reproductive organs in a flower?
Where is the female gamete formed in flowering plants?
Fill in the following blank with suitable word :
Ovules contain ......... gametes of a plant.
Fill in the following blank with suitable word :
The ovule becomes a .......... after fertilisation.
Draw a neat sketch of the stamen of a flower. Mark in it filament and anther.
Draw a neat sketch of the carpel of a flower. Mark in it stigma, style and ovary.
Give some examples of different modes of fertilisation in nature?
In tobacco plant, the male gametes have 24 chromosomes.
What is the number of chromosomes in the zygote?
Which of the following statements are true for flowers?
(i) Flowers are always bisexual.
(ii) They contain sexual reproductive organs.
(iii) They are produced in all groups of plants.
(iv) after fertilization they give rise to fruits.
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?
In what ways is fertilisation in a plant similar to fertilisation in a human?
Put a tick mark (✓) against the correct alternative in the following statement
Reproductive whorls of a flower are:
The students of a class were asked by the teacher to study the different parts of an embryo of an angiosperm. Given below are the essential steps for the experiment :
A. Soak the seeds in plain water and keep them overnight.
B. Cut open the soaked seed and observe its different parts.
C. Take some healthy seeds in a petri-dish.
D. Drain the excess water, cover the seeds with a wet cotton cloth and leave them as it is for a day.
The correct sequence of these steps is
(a) C, A, D, B
(b) C, D, A, B
(c) A, C, D, B
(d) A, C, B, D
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.
Explain the process of fertilisation in flowers.
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
Write the names of male and female reproductive parts of a flower.
What is phototropism?
What is cleistogamy? Write one advantage and one disadvantage of it, to the plant.
__________ is present in unisexual flower.
Give scientific reason.
Flower is a structural unit of sexual reproduction in plants.
Observe the figure below. Write functions of the labelled parts.
Pineapple fruit develops from ______.
In human beings, fertilization occurs in the ______
The ovaries of different flowers may contain
The figure below shows the concept of double fertilization. Complete the flow chart showing the progress at each step:
Sexual maturation of reproductive tissues and organs are necessary link for reproduction. Elucidate.
Name the reproductive parts of an angiosperm. Where are these parts located? Explain the structure of its male reproductive part.
Consider the following three flowers namely X, Y and Z. Which flower(s) would develop into a fruit?
| Flower X | Flower Y | Flower Z |
 |
 |
 |
Explain the post fertilization changes that occur in the ovary of a flower.
