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प्रश्न
Why does the zygote begin to divide only after the division of Primary endosperm cell (PEC)?
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उत्तर
The zygote needs nourishment during its development. As the mature, fertilised embryo sac offers very little nourishment to the zygote, the PEC divides and generates the endosperm tissue which nourishes the zygote. Hence, the zygote always divides after division of PEC.
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संबंधित प्रश्न
Some organisms suspend their metabolic activities to survive in unfavourable conditions. Explain with the help of any four examples.
Describe the development of endosperm after double fertilisation in an angiosperm.
Describe the formation of helobial endosperm
Describe the development of an endosperm in a viable seed. Why does endosperm development precedes embryo development?
Identify the characteristic feature/s of helobial endosperm.
Identify the CORRECT statement/s from the following.
i. In post-fertilization changes within the ovule, the development of embryo is followed by the development of endosperm.
ii. Helobial endosperm is intermediate between cellular and nuclear type endosperm.
iii. Helobial endosperm is mostly observed in 72 families of dicots.
Which of the following triggers an acrosomal reaction of the sperm?
A diploid female plant and a tetraploid male plant are crossed. The ploidy of endosperm shall be ______.
In angiosperms, triple fusion is required for the formation of ______.
Double fertilization leading to initiation of endosperm in angiosperms require ______.
If the endosperm cell of an angiosperm contains 24 chromosomes, the number of chromosomes in the root tip cells will be ______.
The coconut water from tender coconut is ______
Which of the following statements are true related to Seed X and Y?
 |
 |
| SEED X | SEED Y |
- Seed X is dicot and endospermic or albuminous.
- Seed X is dicot and non-endospermic or non-albuminous.
- Seed Y is a monocot and endospermic or albuminous.
- Seed Y is a monocot and non-endospermic or non-albuminous.
Choose the correct option with the respect to the nature of the seed.
The diagram given below shows the three types of endosperms in angiosperms.
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 |
 |
| Type 1 | Type 2 | Type 3 |
- Identify the three types of endosperms shown above.
- Name the type of endosperm which commonly occurs in polypetalous dicots.
The number of chromosomes in the leaf cells of a male plant is 40 and in the stem cells of a female plant is 60. If they are artificially hybridised, what will be the number of chromosomes in the endosperm?
In angiosperm, the haploid, diploid and triploid structures of a fertilized embryo sac sequentially are ______.
