When do mutations not cause a change in amino acid sequence?
The genetic code is degenerate- this means that amino acids can be coded for in more than one way. In an mRNA sequence coding for a protein, each amino acid in the protein is encoded by one codon (set of three nucleotides). Some amino acids can only be coded for by one particular codon (eg tryptophan, UGG) but most can be coded for by at least two different codons which differ in their third letter. This means that if a mutation occurs in the third letter of a codon, there is a significant chance that it will still code for the same amino acid.
It has been suggested that this flexibility is necessary for life to evolve, as it makes natural selection more lenient towards mutations that would otherwise be harmful.
EP
Related Biology A Level answers
All answers ▸Describe the processes that occur at a cholinergic synapse to allow signal transmission
What is the difference between mitosis and meiosis?
An extract of DNA contains 4000 base pairs. The extract is identified to contain 300 guanine bases. How many adenine bases can be found in the DNA extract?.
Putting bee honey on a cut kills bacteria. Honey contains a high concentration of sugar. Use your knowledge of water potential to suggest how putting honey on a cut kills bacteria.