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प्रश्न
In flowering plants, the pollen grains are transferred to stigma by pollination but the female germ cells are present in the ovary.
Explain with the help of a labelled diagram (only concerned parts), how the male germ cell reaches the ovary.
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उत्तर
The pollen particle receives water and nutrients after touching a suitable stigma. It creates a tube known as a pollen tube. Pollen tube develops in the style and travels to the ovary. Two male gametes, or sperm cells, and a tube nucleus may be found at its tip. The advancing pollen tube penetrates the inside of the embryo sac of an ovule, often through the micropyle. The tube ruptures at this point, releasing its two male gametes. To create a zygote, one male gamete unites with one egg.
The action is referred to as syngamy. Endosperm is created when the second male gamete combines with binucleate central cells. Triple fusion is the name given to the process since it includes the fusing of three haploid nuclei. Accordingly, triple fusion is the union of a male gamete with two polar nuclei inside the angiosperm's embryo sac.
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संबंधित प्रश्न
Name the parts labelled as A, B, C and D in the diagram given below:
Which of the following statements are true for sexual reproduction in flowering plants?
(i) it requires two types of gametes
(ii) fertilisation is a compulsory event
(iii) it always results in the formation of zygote
(iv) offsprings formed are clones
(a) (i) and (iv)
(b) (i), (ii) and (iv)
(c) (i), (ii) and (iii)
(d) (ii), (iii) and (iv)
The correct sequence of reproductive stages occurring in flowering plants is ______
State whether the following statement is true (T) or false (F):
Stamens make egg cells.
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
Give scientific reason.
Fertilization in plants is called double fertilization.
The ovule of an angiosperm is technically equivalent to ______
Which type of development is observed in male gametophytes of plants?
Complete the table
| Carly x | ______ | ______ |
| ______ | petal | attract insects |
| Androecium | ______ | Male reproductive part |
| ______ | ______ | Female reproductive part. |
What is the structural unit of sexual reproduction in plant?
