A) fruit flies
B) humans
C) yeast
D) mice
E) zebrafish

A) The theory of pangenesis states that all living organisms are composed of cells.
B) Bacteria and viruses are not useful in studying genes and inheritance because they are structurally and metabolically different from eukaryotic cells.
C) Charles Darwin accurately described the laws of inheritance in his landmark book, On the Origin of Species.
D) Many human traits, such as skin and hair color, are determined by more than a single gene.
E) Evolution can occur without genetic changes in the population.

A) inheritance pattern of gene alleles
B) mechanism of DNA replication
C) gene expression patterns
D) evolution
E) chemical modification of nucleic acids