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प्रश्न
Give scientific reason.
Fertilization in plants is called double fertilization.
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उत्तर
- The pollen grain germinates over the stigma and gives rise to pollen tube.
- The pollen tube bursts and releases two male gametes in the embryo sac.
- One male gamete fuses with the egg cell to form the zygote, whereas the second male gamete fuses with two polar nuclei in the embryo sac to form an endosperm.
- Since, in flowering plants, the process of fertilization occurs twice in the same embryo sac, by two male gametes, it is called as double fertilization.
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संबंधित प्रश्न
Name the parts labelled as A, B, C and D in the diagram given below:-
The anther contains ______.
Name the part made up of the stigma, style and ovary.
Where is the male gamete formed in flowering plants?
Where is the female gamete formed in flowering plants?
Fill in the following blank with suitable word :
Flowering plants reproduce by ...........method of reproduction.
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.
What is made in anther of a flower?
Name the part of a seed which grows into root.
(a) Draw a neat diagram of a flower showing its various parts. In this diagram mark stem, receptacle, sepals, petals, stamen and carpel.
(b) What name is given to (i) all the petals of a flower, and (ii) all the sepals of a flower?
(c) What are (i) stamen, and (ii) carpel, in a flower?
(d) What is the other name of carpel of a flower?
(e) What is the name of yellow powdery substance present in the anther of a flower?
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
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.
Put a tick mark (✓) against the correct alternative in the following statement
Reproductive whorls of a flower are:
Multiple choice question. Tick (✓) the correct choice:
The male gamete is present inside the which germinates.
- the style
- the stigma
- the anther
- the ovary
Fill in the blanks:
A carpel consists of ________ , ________ and ________.
Mention the function of Anther.
Mention the function of Stigma.
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.
Give one example each of unisexual and bisexual flowers. Differentiate between the two types of pollination that occur in flowers. What happens when a pollen lands on a suitable stigma? Write about the events that occur till the seed formation in the ovary.
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
List any two differences between pollination and fertilization.
Fill in the blank by selecting suitable word:
Transfer of pollen grains from the anther to the stigma is known as______________.
Answer the following question.
How does suitable pollination lead to fertilization?
__________ is present in unisexual flower.
Pollen grains from anther are transferred to the stigma.
What does germination mean?
Give scientific reason.
Flower is a structural unit of sexual reproduction in plants.
Explain the sexual reproduction process in plants with a diagram.
The male reproductive part of a flower is ______.
Where does the endothecium layer of anther lobes is present?
Antipodal cells are present towards the ______ in an anatropous ovule.
What would be the number of chromosomes in the cells of the aleurone layer in a plant species with 8 chromosomes in its synergids?
Conidia are formed endogenously while zoospores are formed endogenously.
The flower of the Hibiscus plant is ______
Complete the table
| Carly x | ______ | ______ |
| ______ | petal | attract insects |
| Androecium | ______ | Male reproductive part |
| ______ | ______ | Female reproductive part. |
Where is the zygote located in the flower after fertilization?
The ovaries of different flowers may contain ______.
State the number of sets of chromosomes present in a zygote.
- Assertion: Primary endosperm nucleus is diploid.
- Reason: It is the product of double fertilisation.
