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We are here with Dr. Ruth Tennen to talk about molecular genetics, here at Shmoop Global Headquarters in Mountain View, California.

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Dr. Ruth here is a PhD, trying to cure cancer.

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So if you ever want to make your parents really proud of you, follow in her footsteps.

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I can't think of much better on earth to do with your life...

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Let's just jump right in to Lesson 1 here.

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We're gonna cover genetic code and DNA/RNA structure.

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So, Dr. Ruth, what does DNA stand for? Like...I can't even spell it...

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So DNA stands for deoxyribonucleic acid.

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So all the letters are in there somewhere.

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Nucleic acid is basically any polymer or any group of molecules in your cells that are composed of nucleotides.

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So it has three parts. It has a base made of nitrogen...

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...it has a phosphate group... and it has a sugar.

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Okay, so we gotta back you up.

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Polymer...that's many mer...

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Yes, many mer. That's exactly it.

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You have one unit of molecule, and then you string a bunch of them together. So it's a monomer to a polymer...exactly, just like beads.

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There are a couple other five-dollar words. What is a phosphate group?

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I'm picturing... you go to that old-style Coca-Cola stand with a hot dog and a shake...

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So a phosphate group basically has a phosphorus and some oxygen atoms in it.

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And it forms the backbone of the DNA, so basically it's all along the outside of the DNA molecule...

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...and they link up together to form the chain.

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And a nitrogen base...like...nitrogen's a molecule?

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Nitrogen's another atom.

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And what is its base? The ATCG is adenine, thytozine, cytosine, guanine... if I remember from high school a million years ago...

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If you can, break down the word for us. What is "deoxy"?

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...No longer oxy?

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That's exactly it. It means it's missing an oxygen.

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So basically, in the sugar molecule that's part of the nucleotide...

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...in RNA, there's an extra oxygen compared to DNA.

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So deoxy basically means missing an oxygen.

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Got it. And "ribo"... that's something to do with Eve and Adam...?

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So ribose is just a type of sugar.

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And then nucleic...?

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Yeah, so it's the same idea. The nucleus is made up of these nucleotides.

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So deoxyribo tells us that it's DNA, not RNA, 'cause the sugar is missing an oxygen molecule.

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Okay, so that's what DNA stands for. That's what comprises DNA. But what is DNA? Like, what does it do for us? How does it function...other than to confuse high school children?

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It's actually super important. It's basically the biological blueprint that makes us who we are.

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So it contains all our genetic information. We get half of our DNA from our mom, half from our dad.

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And then every time our cells divide, the DNA gets split into the two cells.

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So it kind of keeps going through all the different cells.

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And what is its primary function? Like, walk us through the creation of the code of proteins and how that kind of builds a human being.

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So in basic terms, you start with the DNA. You get 23 chromosomes from your mom, 23 from your dad. So that's 46 total.

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The DNA codes for an intermediate called RNA, through a process called transcription.

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And the RNA gets turned into proteins, ultimately, and proteins are kind of the workhorses in your cells.

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They do all the work, they form the structures in your body, they do all the enzyme processes.

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So they give you all your traits, they can have things to do with your personality, your appearance, all sorts of things.

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