Biology Is Beautiful (Educational)
Humans have 23 pairs of chromosomes not 24 as was thought.
by Spock the Vegan
Many ‘facts' have changed from when I was taught.
Each chromosome contains from 50 to 2000 genes.
Some of my High School teachers didn't know beans.
The DNA molecule is very complex, but not diabolical.
Every cell of every living organism contains a DNA molecule.
It contains the chemical instructions to create the organism
Including the bones of a working mechanism.
Here are some facts without any formality:
There are more atoms in one DNA molecule than
there are stars in the Milky-Way Galaxy
(204 billion) .
The DNA molecule is a double helix, but there is a separate
smaller circular mitochondrial DNA molecule in each cell.
The former you get half from your father and half from
your mother. The latter you get all from your mother.
Human cells have 46 of the double helix DNA molecules
each. The mitochondrial DNA is duplicated about 8000
times in each cell. With 10 trillion cells in the human
body, that gives about 10 trillion-trillion DNA atoms.
There are an estimated 20,000 to 25,000 genes
in the human genome. The haploid human genome
consists of a total of over 3 billion DNA base pairs.
Scientists have identified about 1.4 million locations where
single-base DNA differences occur in humans.
This information may revolutionize the processes of
finding chromosomal locations for disease-associated
sequences and tracing human history.