(a) “The female gametophyte of an angiosperm is a seven celled, eigh

1.	(a) “The female gametophyte of an angiosperm is a seven celled, eight nuclei containing structure."Justify.(b) Explain double fertilization in angiosperms.
Answer» (a) Eight nuclei in mature Embryo sac - Three cell form an egg apparatus , consisting of one egg cell and two synergids - Three cells at chalazal end called antipodals - A large central cell with two polar nuclei (b) After entering a synergid, pollen releases two male gametes into the cytoplasm - one male gamete fuses with egg nucleus and completes syngamy resulting in zygote - other male gamete fuses with the two polar nuclei located in the central cell to produce a triploid primary endosperm nucleus this is called triple fusion - since two types of fusions take place ---> double fertilisastion

(a) “The female gametophyte of an angiosperm is a seven celled, eight nuclei containing structure."Justify.(b) Explain double fertilization in angiosperms.

Answer»

(a) Eight nuclei in mature Embryo sac
- Three cell form an egg apparatus , consisting of one egg cell and two synergids
- Three cells at chalazal end called antipodals
- A large central cell with two polar nuclei
(b) After entering a synergid, pollen releases two male gametes into the cytoplasm
- one male gamete fuses with egg nucleus and completes syngamy resulting in zygote
- other male gamete fuses with the two polar nuclei located in the central cell to produce a triploid primary endosperm nucleus this is called triple fusion
- since two types of fusions take place ---> double fertilisastion

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