Answer 1:
1. A number of genes associated with breast
cancer have been found. So far, all these genes
are found on non-sex, or somatic chromosomes. This
means that women can inherit them from either
their mother or father.
2. Yes, to become a boy you must inherit a Y
chromosome from your father. Occasionally,
children are conceived with one X and no other sex
chromosomes, they develop as sterile females, with
some other abnormalities (this condition is called
Turners syndrome). The Y chromosome is very
tiny and carries very few genes. The genes it does
carry are mainly regulatory, that is, they
instruct control how other genes located on the
somatic chromosomes behave. So not all the
genes that contribute to male traits like facial
hair, taller height, etc., are on the Y
chromosome, but the genes that control those genes
are.
3. The 2 X chromosomes are different since
females inherit one from their mother and the
other from their father. They carry all the
same genes that code for the same traits, but may
have different alleles of those genes, that
is, the traits on each chromosome may be slightly
different (like brown vs. blue eye color). As
mentioned above, you only need one X chromosome
to become a female, but you need two X chromosomes
to become a normal female. During development,
both X chromosomes are being transcribed in the
embryo. However, at a very early stage, one X
chromosome in each cell condenses into a tiny mass
and becomes non-functional. The other X chromosome
continues functioning. It is completely random
which of the X chromosomes condenses. |
Answer 2:
I think from both. It would depend on which
chromosome those genes are.
The chromosome from your father is the one
that will determine if you are a boy or girl.
You will always get an X from your mother because
she has X and X. Your father has an X and a Y.
If you get an X from him, you will be a girl
because you have XX, if you get a Y from him you
will be a boy because you have XY.
So, yes, the X that males have is the same
as the X females have, and the two X chromosomes
code for the same things. Click Here to return to the search form.
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