The science of macaroni salad: What's in a molecule? - Josh Kurz

314,227 views ・ 2013-08-16

TED-Ed


Please double-click on the English subtitles below to play the video.

00:07
We already know that the world is made of things,
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things like cats
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and macaroni salad,
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and macaroni salad is made of things
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like mayo
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and mustard
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and celery,
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which are all made of molecules.
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As we'll see, these molecules
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are made of the same stuff,
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just mixed together in different ways.
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Let's go back to our macaroni salad.
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We've already unmixed things physically
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as much as we can.
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Now, we'll go further and unmix things chemically
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by breaking some bonds.
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Many larger, complex molecules
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are just a bunch of smaller molecules bonded together
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like building blocks.
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Here, again, macaroni salad provides a nice example.
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If you look at the pasta,
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you'll notice it's made of a lot of this stuff,
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starch,
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which is this molecule,
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otherwise known as amylose.
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Turns out, if you break some bonds,
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amylose is made up of smaller molecules
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of glucose, a simple sugar.
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If you take a bunch of these same glucose molecules
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and rearrange them in a different way,
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you get cellulose,
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which is what plants are made of.
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So, while this piece of pasta made of amylose
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and this wooden spoon made of cellulose
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look vastly different,
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they're both essentially made of the same molecules,
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just stuck together differently.
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This type of breaking apart and recombining
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is what goes on when you digest food.
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The complex proteins found in the foods we eat,
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like carrots and eggs,
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can't be used by our bodies
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because we are not carrots or chickens.
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What we can use are the smaller molecules
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that make up these proteins,
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the amino acids.
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During digestion, our bodies break these proteins up
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into their amino acids
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so they can be rearranged and put back together
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to make human proteins.
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But let's keep breaking bonds.
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All molecules are made up of atoms bonded together.
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If some molecules are building blocks,
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atoms are the building blocks
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of the building blocks.
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And you'll notice that with the molecules
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from macaroni salad,
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the same six types of atoms keep showing up:
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carbon,
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hydrogen,
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oxygen,
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nitrogen,
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phosphorus,
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and sulfur,
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or CHONPS.
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There's a few others,
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but the big six is what macaroni salad is made of.
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If we went a step further,
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we could use these same atoms,
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recombine them,
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and make other stuff
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like gasoline
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or sulfuric acid,
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methane,
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and nylon.
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It's all made from the same elements
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that make up macaroni salad.
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So, to recap,
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everything is made of atoms.
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They are the stuff that things are made of.
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Atoms are grouped together in different ways
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to form molecules.
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These molecules are constantly being combined,
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broken apart,
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and recombined.
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They get thrown into mixtures,
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separated,
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remixed
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over and over and over again.
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The stuff that things are made of
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is always in flux;
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it's always changing.
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Macaroni salad is only macaroni salad for a short time.
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You eat it,
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some of it becomes part of you,
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the rest eventually goes into the ocean
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and gets eaten by other animals that die,
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and after millions of years, they turn into oil,
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which is where gasoline comes from.
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And that's why gasoline and macaroni salad
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are not that different -
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they're both made of the same stuff,
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just one tastes better.
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