Crick and James Watson, finally began to find out
the basics of how genes worked and how they copied themselves.
This was back in 1953 when they discovered what the stuff
that makes all genes everywhere really looked like. This
stuff is called
(for you clever kids, that stands for deoxyribonucleic
acid - got that?) and it looks like a double
corkscrew. It seems that DNA stores all the information
about how to make a new cell - or person or penguin. It
all coils up very small to pack away into the tiny space
in the centre of cells.
How does the DNA copy itself? Because it's made of two
corkscrews - called a double helix - hooked together,
it can unwind. As it does this, it attracts the right
new bits to join the hooks which run down its middle -
a bit like the legs on a millipede.
And so one strand rebuilds a new mirror-image of itself, just as its mirror-image
partner is doing nearby. So one DNA molecule becomes two perfect copies.
Clever stuff, eh?
How the DNA itself then organises all the stuff inside
a cell to make whatever it needs - like proteins - is
complicated. Scientists still don't understand all the
things that have to happen to make what starts as just
one cell into a human being or a whale. It's taken billions
of years for nature to develop all this wonderfully clever
yet tiny machinery to build bodies. So it's not surprising
that scientists don't understand everything yet... which
makes the next bit rather worrying.
to 'Adapt or die'
to 'Welcome to gene tinkering' & 'Evolution on fast