Let's mix up some life.  We will need four ingredients.  What will we need to make life?  Food to eat.  Water to drink.  Air to breathe.  No, TV is not an important ingredient.  What is the last thing?  While food, water, and air may keep life going, not one of them is the most important part.  Bones, skin, muscles, and blood all feel and look very different, but they all grow out of the same stuff.  What are we missing?

Life's ingredient is everywhere, but is not easy to find.  It changes the way it looks, depending on where you find it.  Pencils, plants, your skin, and the air we breathe out all have it.  Carbon is an element that is needed for all life as we know it.  It can connect with many other things to make lots of different and really cool stuff.  How about this?  Sugar would not be here if it wasn't needed to hold all of the atoms together.  Let's look at how this sweet thing works. 

If carbon did not hold things together, it would mean more than no more sugar.  Most of the things we need to stay alive are made with this stuff stuck in between their parts.  To bond means to stick or connect to something else.  You could bond to someone by hugging them and never letting go.  Carbon bonds to other things to make the plastic of your pen and the lead in your pencil.  In fact, it can bond to more things than anything else!  It is like that piece of tape that keeps sticking to EVERYTHING.

Where would we be without sugar?
Leon Brooks, Public domain, via Wikimedia Commons


To get all this stuff to stick together, we need one long piece that it can stick to.  When you hear the word backbone, what do you think of?  How about the spine that holds your body up?  Or the back of a book?  Without backbones, a book's pages would scatter everywhere and your body would fall into a pile of bones.  A backbone is something strong that holds different things together.  Carbon is the backbone for many things on Earth.  It keeps the pages and the leaves of trees and every part of you from scattering everywhere.

Carbon, the backbone of life on our planet.
Sklmsta, CC0, via Wikimedia Commons


That's right, carbon does not start and stop with plastic and pencils.  When one carbon (C) fixes with another to make C-C, it makes the backbone for all the smaller parts we need for life.  Thousands of these fix together to grow your thumb and your toe and your ear and everything in between.  A carbon-based life form is any living thing, plant or animal, that is made of carbon.  This means you and me and almost everything else on Earth that is alive.  You have more in common with pencils and pens than you thought.  That's probably a good and a bad thought.

At least I won't run out of pencils today.
No machine-readable author provided. BiT assumed (based on copyright claims)., Public domain, via Wikimedia Commons


There are many ingredients that make a life: food, water, air.  But only one of them is the most important part for every living thing on Earth.  Carbon is the base for all life because it can bond to many things.  It can make plastics, or if it connects with another carbon it becomes the things that make up all of life as we know it.  Even you. 
 

References:

Chem 4 Kids.  "Carbon"  Chem 4 Kids, 2012.  <http://www.chem4kids.com/files/elements/006_speak.html>

Science Kids.  "Carbon Facts"  Science Kids, 2013.  <http://www.sciencekids.co.nz/sciencefacts/chemistry/carbon.html>

Ducksters.  "Carbon"  Ducksters, 2008.  <http://www.ducksters.com/science/chemistry/carbon.php>