Question

please explain the significance of the three polar bodies formed in oogenesis? Like what is their specific function?

Answer 1

The polar bodies are formed during the process of oogenesis in female reproductive system. The process of oogenesis starts with a diploid primary oocyte which undergo meiosis to form secondary oocyte and first polar body. The secondary oocyte and the first polar body are haploid. This division occurs in the diplotene stage of prophase 1. the primary function of primary oocytes is to divide by the process of meiosis to form female gametes. This division stars in embryonic stage and halted until the puberty. The initiation of this process starts at prenatal age.

After meiosis 1, meiosis II takes place. Meiosis 2 is in fact is a mitotic division of secondary oocyte formed during the meiosis 1. During meiosis 2, the secondary oocyte and the first polar body formed will divide by mitotic division to form one haploid ootid and three haploid polar bodies. The haploid ootid formed is called the ovarian follicle which will be used for fertilization.

When we carefully examine the whole process, we will find that there are 3 polar bodies are formed at last. The size of the polar bodies is too small in comparison to the oocytes on the other hand they carry the same chromosomal set as the oocytes.

The significance of forming these three polar bodies is to conserve the haploid set of chromosomes in oocytes during cell division and also to discard the extra haploid set of chromosomes formed as a result of miosis.

At last, we will get a haploid ovarian follicle after two cell division cycles because the three polar bodies formed during the cell divisions are degenerated.

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