AP BIOLOGY

Detailed explanation-1: -The human arm is composed of the same set of bones, i.e. humerus, radius, and ulna, just as the arms of the other animals included in the figure. The figure shows the bones that make up the different animal forelimbs. Notice that their forelimbs have the same bone components. They are examples of homologous structures.

Detailed explanation-2: -A classic example of homologous structures is that of the wing of a bat and the arm of a human. Both have similar internal bone structure, and as mammals, the evolutionary origin is clearly similar.

Detailed explanation-3: -The wing of a bird and the arm of a human are examples of c. homologous structures. This is because they are structures which have a similar evolutionary origin despite the fact that they play different roles.

Detailed explanation-4: -Analogous organs have a similar function. For example, the bones in a whale’s front flipper are homologous to the bones in the human arm. These structures are not analogous. A butterfly or bird’s wings are analogous but not homologous.

Detailed explanation-5: -However, hands and feet are serially homologous structures that share virtually identical developmental blueprints, raising the possibility that digital proportions coevolved in human hands and feet because of underlying developmental linkages that increase phenotypic covariation between them.