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प्रश्न
What is pollination? Mention its types.
उत्तर
- The process of transfer of pollen grains from another to stigma is called pollination.
- There are two types: Self-pollination and cross-pollination.
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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
How is the process of pollination different from fertilization?
The anther contains ______.
The fusion of male and female gametes is termed as ______.
Sketch the reproductive parts of a flower.
How does the process of fertilisation take place in flowers?
The process of fusion of the male and female gametes is called ______.
Name the male part of the flower.
Draw a neat sketch of the carpel of a flower. Mark in it stigma, style and ovary.
What is made in anther of a flower?
What is seed? What are the parts of a seed? Explain with the help of a labelled diagram.
What changes take place in the flower after fertilisation which lead to the formation of seeds and fruit?
Which of the following is the correct sequence of events of sexual reproduction in a flower?
(a) pollination, fertilisation, seed, embryo
(b) seed, embryo, fertilisation, pollination
(c) pollination, fertilisation, embryo, seed
(d) embryo, seed, pollination, fertilisation
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?
Fill in the blank by selecting suitable word:
A flower that bears both the male and the female parts is known as __________ flower.
State whether the following statement is true (T) or false (F):
Stamens make egg cells.
State whether the following statement is true (T) or false (F):
Flowers which possess stamens and carpel are called unisexual.
What part is played by stamens and carpels in reproduction?
Write one main difference between asexual and sexual mode of reproduction. Which species is likely to have comparatively better chances of survival – the one reproducing asexually or the one reproducing sexually? Give reason to justify your answer.
A student is asked to study the different parts of an embryo of pea seeds. Given below are the essential steps for the experiment :
(I) Soak the pea seeds in plain water and keep them overnight.
(II) Cut open the soaked seed and observe its different parts.
(III) Take some pea seeds in a petri dish.
(IV) 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) III, I, IV, II
(B) III, IV, I, II
(C) III, I, II, IV
(D) III, II, I, IV
“Cell division is a type of reproduction in unicellular organism.” Justify.
Draw a diagram of a pistil showing pollen tube growth into the ovule and label the following:
Pollen grain, male gamete, female gamete, ovary.
Distinguish between unisexual and bisexual flowers giving one example of each. Draw a diagram showing process of germination of pollen grains on stigma and label the following parts:
(a) Female germ cell
(b) Male germ cell
(c) Ovary
Describe an activity to demonstrate phototropism.
Differentiate between self-pollination and cross-pollination.
Answer the following question.
List two agents of pollination?
__________ is present in unisexual flower.
Calyx : Sepals : : Corolla : ________________
The essential parts of a flower are ______.
Write the events involved in the sexual reproduction of a flowering plant.
Discuss the first event and write the types.
Identify the female gametophyte in angiosperms.
Pollen grains are produced by ______
Length of pollen tube depends on the distance between ______
Complete the table
| Carly x | ______ | ______ |
| ______ | petal | attract insects |
| Androecium | ______ | Male reproductive part |
| ______ | ______ | Female reproductive part. |
Double fertilization is essential for formation of ______.
Sketch and label the essential and accessory whorls of flower.
State the post-fertilisation changes that lead to fruit formation in plants.
- Assertion: Primary endosperm nucleus is diploid.
- Reason: It is the product of double fertilisation.
