AP BIOLOGY

Detailed explanation-1: -If two or more species share a unique physical feature, such as a complex bone structure or a body plan, they may all have inherited this feature from a common ancestor. Physical features shared due to evolutionary history (a common ancestor) are said to be homologous.

Detailed explanation-2: -Homologous structures are similar physical features in organisms that share a common ancestor, but the features serve completely different functions. An example of homologous structures are the limbs of humans, cats, whales, and bats.

Detailed explanation-3: -All animals (including humans), plants and other organisms such as fungi and algae are Eukaryotes and share a common ancestor.

Detailed explanation-4: -When two or more organs or structures are basically similar to each other in construction but are modified to perform different functions, they are said to be serially homologous.

Detailed explanation-5: -Homologous structures are structures that are similar in related organisms because they were inherited from a common ancestor. These structures may or may not hav e the same function in the descendants. Figure below shows the hands of several different mammals. They all have the same basic pattern of bones.