<span>The horizontal line present across the front teeth are called perikymata. These are incremental growth lines that appear on the surface of tooth enamel as a series of linear grooves. These lines can be used to assess how long the crown of the teeth formed. </span>
What I know is that amino acid has side chain, amine groupe ,and groupe of carboxyl so what make them difference is side group where the is 20 different R-group which give each individual characteristics
Hello
Your hand went into a shock because of overuse it is a common thing
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