What are amino acids?
Amino acids are molecules made out of hydrogen, oxygen, carbon, and nitrogen atoms (and a little sulphur).
More about hydrogen
What are molecules?
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When did the first amino acids form?
The earliest amino acids formed in space, about 14 billion years ago, before our solar system’s planets even existed.
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When did the planets form?
How old is the universe?
How did amino acids form?
Probably they formed inside chunks of ice. When ultraviolet radiation (energy) from stars shot through the ice, it encouraged molecules to form. Astronomers have found evidence that amino acids are still out there floating around in nebulae in space.
What’s a nebula?
More about radiation
From amino acids to proteins and RNA
When amino acids first came to Earth, they probably came inside these chunks of ice. When the ice later turned to water on a warmer Earth, the amino acids floated around in the water. They eventually linked up to become bigger molecules called ribonucleic acid (RNA) and proteins. These proteins are what all living cells are made of.
What are proteins?
What is RNA?
Different kinds of amino acids
There are twenty different kinds of amino acids. Plants make all of these amino acids themselves, out of the atoms that are their ingredients. Animals (and humans) can only make ten of the twenty different kinds of amino acids, but we need all twenty kinds in order to live. So we have to get the other ten kinds by eating plants, or animals that ate plants.
Eat a lot of different kinds of food
Different amino acids are in different foods, but if you eat milk, eggs, chicken, and bread you will get all of them. If you’re vegan, you can get amino acids from bread, lentils, bananas, peanuts (or peanut butter), and chocolate or red wine. We can’t store amino acids in our bodies, so we have to eat these foods pretty much every day.