Question

In embryo sac, which one commonly develops haustoria
(a) Synergids
(b) Antipodal cells
(c) Oosphere
(d) Central cell

Answer 1

These cells are the three haploid cells present in the embryo sac of flowering plants. They are present just opposite the micropyle. Its function is to provide nourishment to the egg cells and it is rich in lipid content.

Complete answer:
- Antipodal cells are rich in DNA, RNA, total protein, and histones. Antipodal cells help in the nutrition of endosperm because of its enhancement of these metabolites and polytene levels at the nuclear endosperm stage.
- At the chalazal end antipodal cells are located. Antipodals are nutritive in function and they nourish the embryo sac. Substances developed by antipodal cells are helpful in the growth and development of endosperm. So, Haustoria are formed mainly at the chalazal end and penetrate the nuclear tissue to absorb nutrition.
- Both Synergids and antipodal cells develop haustoria in the embryo sac but the haustorial behavior of antipodal cells is known in many plants because antipodal cells are rich in nutritive function as they provide nutrients for the embryo sac. Hence developing haustoria will aid in nutrient absorption from the nearby tissue, that’s why in an embryo sac haustoria is commonly developed by the antipodal cells.
Hence, the correct answer is, ”Antipodal cells”.

Additional information:
- Generally, synergid cells are located in the female gametophyte and these are essential for angiosperm reproduction. The pollen tube during the process of fertilization grows into one of the synergid cells that stop its growth, ruptures it, and then releases its sperm cells that are two in number into this cell.
- Antipodal cells play a very important role in the embryo sac. They are responsible for the supply of nutrition for the whole gametophyte and also take part in the supply of nutrition during embryo formation.
- Oosphere is a large nonmotile egg cell formed in an oogonium and is ready for fertilization.
- Central cells play a critical role in pollen tube guidance during pollination and in endosperm initiation after fertilization.

Note:
- Antipodals are shock absorbers and nourish the embryo sac while synergids provide chemical guidance to developing pollen tubes.
- Many of the time antipodal cells of the female gametophyte acquire glandular properties.