Question

GENETICS
(#21:: included is the paragraph discussing figure 25.2b & figure 25.2b, and question #21)

Humans are not unique in their extensive variation (Figure 25.2a); almost all organisms exhibit phenotypic vari- ation. For instance, lady beetles are highly variable in their spotting patterns (Figure 25.2b), mice vary in color, snails have different numbers of stripes on their shells, and plants vary in their susceptibility to pests. Much of this phenotypic variation is hereditary. Recognition of the extent of pheno- typic variation led Charles Darwin to the idea of evolution through natural selection. Genetic variation is the basis of all evolution, and the extent of genetic variation within a popu- lation affects its potential to adapt to environmental change. In fact, even more genetic variation exists in populations than is visible in the phenotype. A great deal of variation exists at the molecular level owing, in part, to the redundanc of the genetic code, which allows different codons to specify ino acid. Thus, two members of a population can produce the same protein even if their D

Answer 1