Amino Acids Definition: Lesson for Kids

Instructor: Rebecca Gillaspy

Dr. Gillaspy has taught health science at University of Phoenix and Ashford University and has a degree from Palmer College of Chiropractic.

Proteins make up many parts of your body. Your body makes different proteins by linking amino acids together in different ways. Learn about the basic structure of an amino acid and the two types of amino acids.

What is an Amino Acid?

I bet you know that there are 26 letters in the alphabet and that those letters are linked in specific ways to build words. By just changing one letter, you can make a new word with an entirely new meaning.

For instance, do you like to eat 'dessert' or 'desert'? These two words differ in just one letter, but have very different meanings. We eat a yummy 'dessert', not a 'desert', which is a very hot and sandy place.

The 20 amino acids of the human body are like the letters of the alphabet. Amino acids are the building blocks of proteins. Your body links amino acids together in specific ways to build proteins. Changing just one amino acid in a protein makes a new protein with a very different function.

Proteins are complex structures that are sometimes shown like this. Proteins are made of amino acids.

Proteins are found in every cell of your body and make up your muscles, organs, and immune system, so you need a lot of different proteins to make your body work right.

Basic Structure of an Amino Acid

When you look at the chemical makeup of an amino acid, you'll notice that all amino acids contain an amino group and a carboxyl group. What makes one amino acid different from another is its R-group.

The R-group is what makes an amino acid unique.

An amino group is made up of a nitrogen atom and two hydrogen atoms (NH2).

A carboxyl group is made up of a carbon atom, two oxygen atoms, and a one hydrogen atom (COOH).

An R-group is a side chain. It's different in each of the 20 amino acids.

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