Embryo-sac, Biology

Embryo-sac :

Embryo-sac is formed from megaspore mother cell.

  1. In embro-sac, there are 7 cells arranged in 3 groups. The 7 cells are one egg (female gamete), 2 synergids, one central cell (secondary nucleus) and 3 antipodals.
  2. All the cells except secondary nucleus are in haploid condition (n) secondary nucleus is diploid (2n)
  3. The synergids are also known as helper cells. These cells direct the growth of pollen tube towards the egg. They have beak like structure and are situated near the micropylar end.
  4. The 3 antipodals live only for a short duration. They are situated near the chalazal end of the embryo-sac.

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Posted Date: 8/29/2012 6:26:20 AM | Location : United States






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