What makes you you?
About 30,000 specific genes.
101
DNA
Your genes
are stored in
a chemical called
DNA, which looks like a
twisted ladder with four
different types of rung.
The rungs make up a
four-letter alphabet that
spells out your genes,
like letters in a book.
In the genes
Genes are instructions that
build your body and tell it
how to work. Your genes
control many of the things
that make you unique,
like the colour of
your eyes or how
tall you’ll be.
Changing body
Genes don’t control
everything – experience
also shapes you.
If you exercise a
lot, for instance,
your body gets
stronger.
This girl has a gene that allows
her to roll up her tongue. The
boy doesn’t have the gene,
so he can’t do it.
DNA can
split and
copy itself.
Learning to ride
a bike changes your
brain and your
body.
Look in a
mirror and see if you
can roll your tongue. Don’t
cheat by squeezing it with
your lips. Test your
family to see who
has the gene.
In the family
Your genes came from your parents.
Half come from your mother and
half come from your father. If
you look like your parents, it’s
because you share the same genes.
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