Sunday, May 31, 2020

REPRODUCTION in ANGIOSPERMS - EMBRYO SAC

EMBRYO SAC / FEMALE GAMETOPHYE
  • Haploid (n)
  • Develop from one functional haploid megaspore, so called, monosporic development.
  • Cell division - mitotic nuclear division.

  • Mature gametophyte has- 
  • 7 cells= 3 antipodal cells + 2 synergids + 1 egg cell ( female gamete) + central large cell
  • 8 nuclei = 3 antipodal nuclei + 2 synergid nuclei + 1 egg cell nuclei + 2 polar nuclei
  • So, embryo sac is in 7 celled, 8 nucleated stage.
  • 2 synegids + 1 egg cell = egg apparatus
  • Synergids have special structure- filliform apparatus
  • Filliform apparatus- it guides the pollen tube into embryo sac towards egg cell.

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