How does a 4-letter code build a human?
AI-generated illustrated lesson. Hand-drawn and narrated, step by step.
Molecular Genetics
You've probably heard that DNA is the blueprint of life, but blueprints are just paper. How does a physical molecule actually store information? Meet the double helix: two long chemical backbones twisted around each other like a spiral staircase.
The secret isn't in the twisting staircases, but in the steps connecting them. These are made of just four chemicals, which we call A, T, C, and G. And they have a strict rule: A only ever locks together with T, and C only ever bonds with G.
Because of this strict pairing, if you know one side of the ladder, you automatically know the other. By reading the sequence of these letters down one side, you are reading the literal, chemical code that tells your cells exactly how to build you.
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