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  • We already know that the world is made of things,

  • things like cats

  • and macaroni salad,

  • and macaroni salad is made of things

  • like mayo

  • and mustard

  • and celery,

  • which are all made of molecules.

  • As we'll see, these molecules

  • are made of the same stuff,

  • just mixed together in different ways.

  • Let's go back to our macaroni salad.

  • We've already unmixed things physically

  • as much as we can.

  • Now, we'll go further and unmix things chemically

  • by breaking some bonds.

  • Many larger, complex molecules

  • are just a bunch of smaller molecules bonded together

  • like building blocks.

  • Here, again, macaroni salad provides a nice example.

  • If you look at the pasta,

  • you'll notice it's made of a lot of this stuff,

  • starch,

  • which is this molecule,

  • otherwise known as amylose.

  • Turns out, if you break some bonds,

  • amylose is made up of smaller molecules

  • of glucose, a simple sugar.

  • If you take a bunch of these same glucose molecules

  • and rearrange them in a different way,

  • you get cellulose,

  • which is what plants are made of.

  • So, while this piece of pasta made of amylose

  • and this wooden spoon made of cellulose

  • look vastly different,

  • they're both essentially made of the same molecules,

  • just stuck together differently.

  • This type of breaking apart and recombining

  • is what goes on when you digest food.

  • The complex proteins found in the foods we eat,

  • like carrots and eggs,

  • can't be used by our bodies

  • because we are not carrots or chickens.

  • What we can use are the smaller molecules

  • that make up these proteins,

  • the amino acids.

  • During digestion, our bodies break these proteins up

  • into their amino acids

  • so they can be rearranged and put back together

  • to make human proteins.

  • But let's keep breaking bonds.

  • All molecules are made up of atoms bonded together.

  • If some molecules are building blocks,

  • atoms are the building blocks

  • of the building blocks.

  • And you'll notice that with the molecules

  • from macaroni salad,

  • the same six types of atoms keep showing up:

  • carbon,

  • hydrogen,

  • oxygen,

  • nitrogen,

  • phosphorus,

  • and sulfur,

  • or CHONPS.

  • There's a few others,

  • but the big six is what macaroni salad is made of.

  • If we went a step further,

  • we could use these same atoms,

  • recombine them,

  • and make other stuff

  • like gasoline

  • or sulfuric acid,

  • methane,

  • and nylon.

  • It's all made from the same elements

  • that make up macaroni salad.

  • So, to recap,

  • everything is made of atoms.

  • They are the stuff that things are made of.

  • Atoms are grouped together in different ways

  • to form molecules.

  • These molecules are constantly being combined,

  • broken apart,

  • and recombined.

  • They get thrown into mixtures,

  • separated,

  • remixed

  • over and over and over again.

  • The stuff that things are made of

  • is always in flux;

  • it's always changing.

  • Macaroni salad is only macaroni salad for a short time.

  • You eat it,

  • some of it becomes part of you,

  • the rest eventually goes into the ocean

  • and gets eaten by other animals that die,

  • and after millions of years, they turn into oil,

  • which is where gasoline comes from.

  • And that's why gasoline and macaroni salad

  • are not that different -

  • they're both made of the same stuff,

  • just one tastes better.

We already know that the world is made of things,

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B2 TED-Ed macaroni salad stuff gasoline cellulose

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

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    VoiceTube posted on 2014/03/31
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