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प्रश्न
Assertion: Sporopollenin preserves pollen in fossil deposits
Reason: Sporopollenin is resistant to physical and biological decomposition
विकल्प
assertion is true; reason is false
assertion is false; reason is true
Both Assertion and reason are not true
Both Assertion and reason are true
उत्तर
Assertion is false; reason is true
संबंधित प्रश्न
Triple Fusion involves:
(i) Fusion of one male, gamete with female gamete
(ii) Fusion of tube nucleus with generative nvcleus
(iii) Fusion of two polar nuclei.
(iv) Fusion of second male gamete with two polar nuclei
(a) Explain the events after pollination leading to the formation of a seed in angiosperms.
(b) Mention the ploidy levels of the cells of different parts of an albuminous seed.
Explain the following term:
Elephophily
Given ahead is a diagrammatic sketch of the sectional view of a germinating pollen grain. Study the same and then answer the question that follows:
Where does the germination of the pollen grain take place and how?
Given ahead is a diagrammatic representation of the process of fertilization. Study the same and then answer the question that follows:
Name the parts labelled 1, 2, 3, 4, 5 and 6.
What is the function of pollen tube? Explain with the help of a diagram.
Even though each pollen grain has 2 male gametes, why at least 20 pollen grains are required to fertilize 20 ovules in a particular carpel?
Why fertilization process in angiosperms is called as double fertilization?
The seed is a fertilized _______.
After fertilization the ovule becomes ______.
Which of the following represent megagametophyte
Name the cell which divides to form male nuclei.
Which of the following happens during triple fusion?
In angiosperms, for formation of which of the following triple fusion is necessary?
By which of the following double fertilization is exhibited?
What would be the number of chromosomes in the megaspore mother cell of the plant if an endosperm of an angiosperm has 24 chromosomes?
Double fertilization was first discovered by Nawaschin (1898) in ______.
The female gametophyte of a typical dicot at the time of fertilisation is ______.
Ovules fall off after fertilization.
Which are the three cells found in a pollen grain when it is shed at the three celled stage?
