SEX DETERMINATION IN HUMANS
In humans, sex is determined by sex chromosomes (XX females, XY males).
In humans (as well as many other animals), males generally have one X and one Y chromosome, ( Male Heterogamety )while females have two X chromosomes.
( XX - XY System )
Human sex is determined by the presence or absence of a Y chromosome.
Chromosomal sex is determined at the time of fertilization; a chromosome from the sperm cell, either X or Y, fuses with the X chromosome in the egg cell.
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