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Stated Clearly presents:
what is DNA
and how does it work
DNA also known as deoxyribonucleic acid
is a molecule
it's a bunch of atoms stuck together
In the case of DNA, these adoms combined to form the shape of a long
spiraling ladder
sort of like this one here
if you ever studied biology or watched the movie Jurassic Park, you probably heard
that DNA acts as a blueprint or recipe for living thing
but how?
how on earth can a mere molecule act as a blueprint for something as complex and
wonderful as a tree
a dog or a dinosaur
Yelp!
to help answer that question
let's first take a quick look at amino acids
amino acids are tiny little chemicals inside our bodies that are so important
they're often referred to as the building blocks of life
there's about twenty different kinds each with their own unique shape
the cool thing about them is they can be attached to each other kind of like
Legos to produce an endless variety of larger particles particles called proteins
amino acids make up proteins
proteins along with other chemicals combined to form living cells
cells make up tissues
tissues make up organs
and organs
when they're all put together and functioning of course
combined to form living creatures like you and me
these proteins that make up our bodies and keep in mind there's millions of
different kinds of proteins
they each have to be formed in the perfect shape in order to function
if they are the wrong shape they usually won't work
that's where DNA comes in
DNA does a lot of interesting things
some of which we don't fully understand
but one of its main and most well understood functions is to tell amino
acids
how to line up and form themselves into the perfect
protein shapes
in theory
if the right proteins are built at the right time and in the right place
everything else from cells to organs to entire creatures
will come out just fine
this here is a simplified model of DNA
it shows us that the steps of the ladder
are made up of four different kinds of chemicals shown here by different colors
and letters
if you look at just one half of the molecule
you can read this chemical sequence or genetic code from top to bottom sort of
like a book
a single strand of DNA
is extremely long
millions of letters long
it spends most of its life coiled up like a noodle living inside the nucleus
or the centerpiece of a cell
amino acids however live outside the nucleus in what's called the cytoplasm
to help DNA interact with the cytoplasm and convert those amino acids
into proteins
special chemicals inside the nucleus make partial copies of the DNA code
these partial copies called RNA
look a lot like DNA but they're shorter of course and they're missing
one of their sides
their small shape and size allows them to fit through tiny pores in the nucleus
out to the cytoplasm and into the mouth of another particle called a ribosome
ribosomes are protein building machines
they the RNA code three letters at a time
suck amino acids out of their surroundings stick them together in a
chain according to the genetic code
as a chain grows it bends, folds, and sticks to itself
to form a perfectly shaped
protein
every three letters of the RNA code
tell the ribosome which of the twenty different kinds of amino acids should be
added next
for example CAA tells the ribosome to grab
a glutamine
AGU tells it to grab a serine
and so on
once a protein is built it then goes on to do a number of different things, one
of which could be to help form of brand
new cell
so to answer the original question
what is DNA?
DNA is a molecular blueprint for a living thing
how does it work?
DNA creates RNA
RNA creates protein
proteins
go on to form life
this entire process
as complicated, sophisticated
and magical as it might seem
is entirely based in chemistry
it can be studied
it can be understood
i'm Jon Perry and that's DNA
Stated Clearly
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Learn more about DNA at StatedClearly.com
www.StatedClearly.com
til next time
stay curious