Essential Genetics 6th Edition by Daniel Hartl

Exercise 18

Suppose a primitive living organism is discovered on Mars. It has a genetic system similar to our own in that the sequence of subunits in the genetic material (nucleic acid) is used as a code to specify the linear sequence of subunits of a different type of molecule (protein). In this organism, the nucleic acids are made up of four kinds of nucleotides, but the proteins contain only five kinds of amino acids. The organism produces 100 different proteins, each 10 amino acids in length.
(a) What is the minimum allowable number of bases in a codon in this organism?
(b) In order to make the 10 proteins, what is the minimum number of nucleotides in the genome of the organism?