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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

  • thanks for watching

  • share with friends on facebook or twitter

  • or where ever

  • subscribe to us

  • if you have any questions or comments you can post those in the comments

  • section

  • Learn more about DNA at StatedClearly.com

  • www.StatedClearly.com

  • til next time

  • stay curious

Stated Clearly presents:

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什麼是DNA,它是如何工作的? (What is DNA and How Does it Work?)

  • 107 14
    Jenkai 發佈於 2021 年 01 月 14 日
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