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# biology help watch

1. im so confused rn can someone pls explain how many different combinations of triplet codes you can get? i understand that if one base coded for one amino acid you could only have 4 different amino acids, and if two bases coded for an amino acid there would be 16 different amino acids? but what abt 3, is it???? idk i feel really stupid can someone explainnnn how they find it out too pleasee
2. 64
3. (Original post by valbrechts)
64
yh but can u explain?
4. (Original post by valbrechts)
64
and plus if there can be 64 different combinations then why do people say you can only make 20 amino acids???
5. (Original post by lily.b9)
yh but can u explain?
4 nitrogenous bases, 3 per codon

so: 4^3 = 64.

You seriously dont need to know how to find this out though
6. (Original post by lily.b9)
and plus if there can be 64 different combinations then why do people say you can only make 20 amino acids???
An amino acid can be coded for by more than one triplet code
7. (Original post by lily.b9)
and plus if there can be 64 different combinations then why do people say you can only make 20 amino acids???
Codons are degenerate. This means that 1 amino acid can be coded by more than 1 codon.
8. 4^3= 64 (4 bases, codon=3 bases)
There are 20 different amino acids
More then 1 codon codes for the same amino acid (degenerate code) to reduce effect of mutation

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