In prokaryotes new mutations accumulate quickly in populations, while in eukaryotes new mutations accumulate much more slowly.
The primary reasons for this are:.
A) Prokaryotes have short generation times and large population sizes.
B) Prokaryotes have random mutations while eukaryotes can target genes for mutations; thus mutations may not accumulate as quickly in eukaryotes but they are more useful to the organism.
C) The DNA in prokaryotes is not as stable as eukaryotic DNA and is thus more likely to mutate.
D) Prokaryote mutations are less effective than eukaryote mutations in providing variation for evolution.