A human female forms how many eggs from one original cell?
A human ovary produces a single mature egg (ovum) from millions of immature germ cells (oogonia).
1. Primordial germ cells (PGCs): These are the earliest germ cells, formed during embryonic development. In a female fetus, PGCs migrate to the ovaries.
2. Oogonia: PGCs multiply by mitosis to become oogonia. Each oogonium is a diploid cell with 46 chromosomes.
3. Primary oocytes: At puberty, oogonia enter meiosis, the process of cell division that produces gametes. The first round of meiosis produces primary oocytes, which are also diploid cells.
4. Secondary oocytes: Primary oocytes undergo the second round of meiosis to form secondary oocytes, which are haploid cells with 23 chromosomes.
5. Mature eggs (ova): Secondary oocytes are released from the ovary into the fallopian tube during ovulation. If an egg is fertilized by a sperm, it develops into an embryo. If it is not fertilized, it is reabsorbed into the body.
So, from one original germ cell, a woman produces only one mature egg through the complex process of meiosis and cellular development.