The main difference between prokaryotic and eukaryotic cells is that
a. prokaryotic cells are always much larger.
b. prokaryotic cells do not have a plasma membrane.
c. eukaryotic cells have a smaller cell nucleus.
d. eukaryotic cells have a more complex cellular organization

Which of the following factors would not contribute to allopatric speciation? a) the isolated population is exposed to different selection pressures than the ancestral population.b) a population becomes geographically isolated from the parent population. c) gene flow between the two populations is extensive.d) the separated population is small, and genetic drift occurs. e) different mutations begin to distinguish the gene pools of the separated populations.