Rikard's evolving page!
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Evolution!
I am interested in human evolution. Humans in an evolutionary contest
[could have meant context] means hominidae and includes the great apes
as well [all of us must have done OK in the contest to still be around].
It is not that simple but I will try to say a few words about
DNA [Deoxyribo Nucleic Acid]
The carriers of heredity are our chromosomes inside the nucleus of the cell.
Humans have 46 chromosomes in every cell of the body (except for some certain
cells in the reproductive organs). You inherit 23 from your mother and the
other half from your father (Dolly, the sheep is probably a rare exception,
although non-human[?]). 22 of them are so-called autosomes, i.e. they come
in pairs, one from each parent. The sex-chromosomes determine who you are.
The backbone structure of the chromosomes are DNA.
DNA is a huge string of bases put together in a specific order
and thereby taking charge [together with an immense number of
factors that I am not even trying to mention] of what the cell is doing.
I only want to use this information to try to find out a few things about
ourselves, like background, relation to the apes etc.
Why, The chromosome?
Males are unique, or have a unique feature of their cells. They have two different
sex-chromosomes, one X and one Y. So what?
Since the Y chromosome is alone, it doesn't have anyone to form a couple with (except
for X, also alone in males) it is easier to use this chromosome for structural studies.
You don't have to worry that your chromosomal fragment are derived from different
chromosomes in a pair. Which would be the case for all other chromosomes, including
X in females.
This chromosome is also being sequenced (Whitehead
Institute/MIT Genome Sequencing Project) despite being so tiny.