Mutation - A random change in DNA that alters the sequence of bases
Changes in the base sequence caused by mutations are permanent and heritable (can be passed on)
A mutation can be a change in one base, several bases, or whole sections of chromosomes
Mutations can arise spontaneously during DNA replication or at other points in the cell cycle
Mutations change the base sequence of DNA which changes the codon and this MAY change the amino acid, but this will depend on the type of mutation and where
Degenerate - Several codons code for one amino acid
Most mutations do not alter the polypeptide, or only alter it slightly so that its structure or function is not changed
This is because the genetic code is degenerate (several codons code for one amino acid)
Due to the degenerate nature of the genetic code, not all base substitutions cause a change in the sequence of encoded amino acids
Coding strand - The DNA copy of the mRNA strand that is built on the template strand
Template strand - Where the mRNA is constructed
tRNA anticodons
These are complementary to the codon and each tRNA with a different anticodon carries a different amino acid
This is how the codon is translated
Gene mutations involve a change in the base sequence of chromosomes
