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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:-
State significance of pollination.
Name the parts labelled as A, B, C and D in the diagram given below:
Mention the changes a flower undergoes after fertilisation.
How is the process of pollination different from fertilization?
Explain what you understand by sexual reproduction.
State the name of the functional unit concerned with sexual reproduction.
Where are a plant's sex organs located?
Fill in the following blank with suitable word :
Ovules contain ......... gametes of a plant.
Fill in the following blank with suitable word :
The name of the structure in the flower in which the male gamete is formed is...........
Fill in the following blank with suitable word :
The.......... at the base of the carpel contains egg cells.
What is made in ovary of a flower?
What type of plants reproduce by sexual reproduction method?
What is meant by ‘unisexual flowers’?
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
The length of pollen tube depends on the distance between :
(a) pollen grain and upper surface of stigma
(b) pollen grain on upper surface of stigma and ovule
(c) pollen grain in anther and upper surface of stigma
(d) upper surface of stigma and lower part of style
The correct sequence of reproductive stages occurring in flowering plants is ______.
Fill in the blanks:
A carpel consists of ________ , ________ and ________.
Fill in the blanks:
A stamen consists of ______ and ________.
Mention the function of Stigma.
Identify A, B, C and D in the given diagram and write their names.
(a) Identify A, B and C in the given diagram and write their functions.
(b) Mention the role of gamete and zygote in sexually reproducing organisms.
Write the names of male and female reproductive parts of a flower.
Identify the odd. Stigma, Style, Pollen, Ovary.
A student is observing the temporary mount of a leaf peel under a microscope. Draw a labelled diagram of the structure of stomata as seen under the microscope
Find the odd one out:
Find an odd one out.
Bisexual : Hibiscus : : Unisexual : ___________
Pollen grains from anther are transferred to the stigma.
Define.
Inflorescence
What does germination mean?
Draw a neat and labelled diagram.
Double fertilization in angiosperms
Match the following
| 1. | Petal | Opuntia |
| 2. | Fern | Chrysanthemum |
| 3. | Phylloclade | Attracts insect |
| 4. | Hooks | Spore |
| 5. | Sucker | Bignonia |
Write the events involved in the sexual reproduction of a flowering plant.
a. Discuss the first event and write the types.
b. Mention the advantages and the disadvantages of that event.
Which of the following is the outermost protective layer of anther?
Gloriosa superba exhibits ______.
In a flowering plant, archesporium gives rise to ______.
In a bisexual flower inspite of the young stamens being removed artificially, the flower produces fruit. Provide a suitable explanation for the above situation.
The figure below shows the concept of double fertilization. Complete the flow chart showing the progress at each step:
