Question

Read each example in the left column of the chart. Then, choose a term from the list below the chart that best matches each example. Each term may be used more than once.

Examples: Matching term:
Humans and chimpanzees share some DNA and protein
sequences.

Whales, bats, and birds have the same bone that connects their
limbs to the middle of their bodies.

Used to determine the age of fossils.

A predecessor that a creature shares with another creature.

A scientist studies the distribution of extinct and modern ferns
in North America.

Chicken, pig, and fish embryos all have pharyngeal folds.

If the environment changes, some species may evolve over
time to cope with the differences.

Alligators and humans show similar bone components.

Two species that are said to arise from the same species.


List of Terms:

bio-geography developmental homology
structural homology common ancestor
molecular homology radioactive dating

Answer 1

Homologous structures are features shared among organisms due to common ancestry. Examples include the shared DNA and protein sequences between humans and chimpanzees, as well as similar bone components in alligators and humans.

Homologous structures are features that overlap both morphologically and genetically and are shared among organisms due to common ancestry.

In the examples provided, humans and chimpanzees sharing DNA and protein sequences, as well as alligators and humans having similar bone components, are instances of homologous structures.

Similarly, the presence of pharyngeal folds in chicken, pig, and fish embryos is another example of homologous structures.