You can probably name a lot of things that keep you alive.  Let's see . . . Air.  Food.  Water.  Heat.  These are all things you can see or at least feel in the world.  But there are parts of the things that keep you alive that you cannot see and you might not know about.  These are the building blocks of the universe, and they're so tiny that they might as well be invisible.  So, let's take a moment and meet some of these invisible helpers that help you live, shall we?

Let's start with a simple question.  What are you made of?  Bones and skin and muscle and hair.  What are those made of?  What if I were to tell you that each of those things is mostly made out of water?  Most?  Let's pretend that this glass is you.  Start pouring water into it and I'll tell you when to stop.  Keep going . . . Keep going . . . Keep going . . . There!  Almost 3/4ths of the glass is full.  Oxygen is a gas that makes up 20% of the world's air.  It is part of the water that makes up most of your body.  You breathe it in and your blood also takes it to all the cells in your body to help you to get energy from the food you eat.  If we are mostly made of water, why don't we just breathe water instead of air?  Well . . . because that would really hurt.

We're 3/4 water? No wonder I sweat so much in the summer.

There may be a lot of water in you, but you do not splash all over the place.  That's because you have something that holds everything together and keeps you alive.  Carbon is the base for all living things because it is the friendliest element ever and can join with many different building blocks.  It gets along with more things than anything else on Earth.  You will find it everywhere, from floating in the air to inside your food as sugar.  Isn't that sweet?  Let's pour this carbon into the glass of water.  Keep going . . . stop!  You are made of 18% carbon.  No wonder people like you so much.  You are made of some of the nicest stuff.

Coal is only one form of carbon.

Let's take a break from you for a second and look at the sky.  There is a lot of stuff out there.  Planets!  Stars!  Gases!  But did you know that all of these are mostly made of the same stuff?  Hydrogen is the lightest element.  We often see it as a gas and there is more of it in the universe than anything else.  It makes up 75% of everything we know of, including things like water, sugar, and the sun.  It is to the universe what water is to your body.  Here pour this . . . gas into the glass.  And stop.  You only have about 10% of hydrogen in you.  That's a good thing.  If you had any more, you might be a lot more spacey.

Wait a minute. If the stars are made of hydrogen, and I'm made of hydrogen; does that make me a star? I think so!

What are we going to fill the rest of this glass up with?  There is not a lot of room left.  Here, lift the glass.  See?  It's heavy.  You just used your muscles to pick that up.  Nitrogen is a gas that makes up most of our air and it's one of the things you use to build proteins.  You get this stuff from plants when you eat them or eat something that ate plants.  You know how I told you that oxygen makes up 20% of the air?  Nitrogen makes up another 78%!  Go ahead and pour this . . . other gas into the glass.  Stop!  We do not want it to spill.  Now use your muscles to lift this almost full glass and drink this water.  You need to keep up that 75%.

There are things you cannot see that help you live.  Oxygen lets you breathe and helps you get energy from your food.  Carbon is the stuff that holds all of you together as well as many other things in the world.  Hydrogen is part of water and it helps make every cell in your body.  Nitrogen helps you make proteins which make you strong.  So take a second to thank these helpers that you cannot see.  Or do not.  They will keep you alive either way.


Science Kids.  "Oxygen Facts"  Science Kids, 2009.  <>

Science Kids.  "Carbon Facts"  Science Kids, 2009.  <>

Science for Kids!  "Carbon"  Science for Kids, 2010.  <>

Science Kids.  "Hydrogen"  Science Kids, 2009.  <>

Ducksters.  "Elements for Kids: Hydrogen"  Ducksters, 2012.  <>

Science Kids.  "Nitrogen"  Science Kids, 2009.  <>