genetics biology

1.     a. Consider the following types of substitution mutations. Make a table describing the DNA mutation, the effects on the protein and the possible effects on the cell:


transition, transversion, missense, nonsense, neutral, silent and frameshift


b. Consider a protein that has the following sequence of amino acid.  This is the wild type protein sequence.


            Met – Thr – Cys – His – Ser – Ser …


Mutations of the DNA have led to the following protein sequences.  In each case, provide an explanation of a mutation or mutations that are most likely to have could have occurred.  Discuss how these mutations will effect the cell.


                        a.  Met –  Thr – Ser – His – Ser – Ser …

b.  Met – Thr

c.  Met – Thr – Leu– Ser – Phe – Phe ……


            c. Codons for the same amino acid tend to differ only by the third base position.  Why?