Proteins play countless roles throughout the biological world, from catalyzing chemical reactions to building the structures of all living things. Despite this wide range of functions, all proteins are made out of the same twenty one amino acids, but combined in different ways. The way these twenty amino acids are arranged dictates the folding of the protein into its unique final shape. Since protein function is based on the ability to recognize and bind to specific molecules, having the correct shape is critical for proteins to do their jobs correctly.

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Story by: David S. Goodsell and Maria Voigt
Animation and Editing by: Maria Voigt
Narration by: Brian Hudson