Here is a complete chart of which combinations will result with which proteins:
For evolution to have occurred, genetic mutations are a must. However, not just any mutation would do: it has to be a beneficial mutation in order for natural selection to work (natural selection being the survival of the fittest, or the animal with the best survival traits lives to reproduce).
There are three basic types of mutations: Nucleotide Substitutions, Nucleotide insertion or deletion, and Chromosomal Mutations.
Now let me describe nucleotides: A nucleotide is a chemical that your body uses in its genes, which are all read in series of threes (called codons). There are 5 basic chemicals that make up a nucleotide: Adenine, Thymine, Guamine, Uracil, or Cytosine (from this point on I will use the first letter of each chemical to represent it). The body reads these nucleotides, and with every codon it either produces a protein or stops the reading process (for instance, the sequence GUU will produce the protein valine, while UAA will stop the reading process.
Here is a complete chart of which combinations will result with which proteins:
Nucleotide substitutions is the replacement of one nucleotide by another. For instance, if there were a series of nucleotides that read "GUU CAU UUG", a substitution could result with a reading of "GUU CAU UAG."This changes the series from being a val his leu to being a val his STOP.
Within this category of mutations, there are three sub-categories: Silent, Mis-sense, and nonsense.
More soon.