DNA II

Egg has 23 pairs of chromosomes, sperm 23 pairs chromosomes -> meiosis (reduction) = 23 pairs

A female has only X chromosomes, however a male has both X and Y chromosomes (thus it is more likely to have a girl?)

If there is an extra chromosome, it means that the person has down syndrome.

Turner's syndrome = XO (O has 22 pairs of chromosomes but not X chromosome)
Klinelfer's syndrome = XXY (this is a male that has both sexual organs, e.g. have male genitalia but have breast development.)
Super Male = XYY (with this extra Y chromosome, more male hormones produced. The person may be more aggressive)
Super Female = XXX
-> may suffer from other things, like intelligence is lower, THESE PEOPLE ARE MOSTLY STERILE
when you have 2, one is suppressed and one is expressed
when you have 3, the other 2 is suppressed and one is expressed

All homosapiens need at least 1 X chromosome. A Y chromosome by itself will be aborted.

Sometimes, due to the body rejecting the genetic defects of the child, the child may be aborted (e.g. after 2 weeks of pregnancy sudden miscarriage)

DNA cannot be in a chromosome all the time (chromosomes are genes wrapped around a protein)
2 repressive genes will be expressed

O- OO
A- AA/AO
B- BB/BO
AB
think my parents are AO and OO since I have a brother who is A too.

Homework: read up on DNA (: