Xy xy chromosomes 170341-Xy and xy chromosomes
The normal chromosomes for woman are XX, while for men they are XY Back in 1905, being identified as the sexdetermining chromosome, the Y chromosome is being studied Shortly after, biochemists started to study the "sex hormones";If that sperm cell fertilizes a normal egg cell with one X chromosome, the resulting child will have two X chromosomes and two Y chromosomes in each of the body's cells In a small percentage of cases, 48,XXYY syndrome results from nondisjunction of the sex chromosomes in a 46,XY embryo very soon after fertilization has occurredAnswer (1 of 3) The XX/XY system found in humans only goes back the the first Therian (common ancestor of placental mammals and marsupials) This goes back back 170 million years ago, as opposed to the first mammal (nearest common ancestor of human and platypus) which goes back to about 5 mya X And Y Chromosomes With Dna On A White Background Chromosomal Definition Of Female Xx And Xy and xy chromosomes ...