Properties of the Genetic Code

Ordered

Codons for an amino acid are group and codons for amino acids with similar properties are also grouped (ex. basic amino acids grouped together) *Diagram 2*

External punctuation

External codons signal the start and stop and determine the reading frame. AUG (methionine) is the only start codon. There are 3 stop codons. An open reading frame (orf) has 5' untranslated region (UTR), start codon, encoded amino acids, stop codon, and a 3'UTR *Diagram 3*

No internal punctuation

Once you start reading, you don't stop until you reach the end. You read every nucleotide.

Co-linear

The beginning of the gene corresponds to the beginning of the protein; the same applies for the middle and end. (If applicable, introns are spliced out.)

Universal (almost)

The codon charts are for the nuclear code in most organisms but chloroplasts and mitochondria do it slightly different, as they have their own chromosomes

Non-ambiguous

The nuclear genetic code does not change

Degenerate

There are multiple codons for each amino acid. Out of 64 codons , 61 coding and 3 noncoding codons some amino acids are only coded for by one codon; whilst for others there are six different codons that can get you that particular amino acid

Properties of the genetic code

Triplet code Non-overlapping No internal punctuation Degenerate Non-ambiguous Co-linear Universal Ordered

Non-overlapping

codons do not overlap if they did, mutations would be 3x as disastrous for the protein, and the protein would be "locked in" to certain amino acids following each other the "nearest neighbor" of any amino acid can be any other amino acid

Link to diagrams in all info

https://docs.google.com/document/d/15z-641Tec4eiWXVcbGTFb_QgkjitELqUH6-gvMAwFqo/edit?usp=sharing