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meiotic division in oocytes

Meiosis is a type of cell division. It occurs in gametes where the number of chromosomes needs to be halved.

Meiotic division is a type of cell division that occurs in gametes. Oocytes are the progenitor cells which develop into mammalian eggs, or ova. In meiosis in humans, the diploid ‘mother’ cell containing all 46 chromosomes splits into two ‘daughter’ cells, each containing 23 chromosomes. In order for meiosis to function correctly, the meiotic spindle is separated at opposite ends of the cell. It then shoots out microtubules which segregate the chromosomes.

Faults in meiosis can lead to aneuploidy. Aneuploidy is a genetic condition where a cell has an abnormal number of chromosomes. This could be because two chromosomes failed to separate, leaving one daughter cell with two copies and the other with none. Aneuploidy of autosomal chromosomes in living individuals is uncommon as it is often lethal in embryonic development. In contrast, aneuploidy affecting sex chromosomes is more common and can lead to offspring with sex chromosome disorders such as Klinefelter’s or Turner’s syndromes.

This image was inspired by research by Melina Schuh