What term refers to a structure present in an organism that no longer serves its original function?

What term refers to a structure present in an organism that no longer serves its original function?

• A. Functional Structure
• B. Analogous Structure
• C. Vestigial Structure
• D. Homologous Structure

Answer: (C)

The term that refers to a structure present in an organism that no longer serves its original function is known as a vestigial structure. These structures provide insight into the evolutionary history of a species, as they are remnants of features that were functional in ancestral species but have since diminished in utility in modern organisms. A classic example is the human appendix, which is a reduced form of a larger cecum found in herbivorous ancestors that helps digest cellulose. In contrast, functional structures are those that have a current and essential role in an organism's life processes. Analogous structures are features in different species that serve similar functions but evolved independently, showing convergent evolution. Homologous structures are similar in form due to shared ancestry but may serve different functions in the present. Understanding vestigial structures helps to illustrate how organisms adaptively change over time while retaining traces of their evolutionary past.

The term that refers to a structure present in an organism that no longer serves its original function is known as a vestigial structure. These structures provide insight into the evolutionary history of a species, as they are remnants of features that were functional in ancestral species but have since diminished in utility in modern organisms. A classic example is the human appendix, which is a reduced form of a larger cecum found in herbivorous ancestors that helps digest cellulose.

In contrast, functional structures are those that have a current and essential role in an organism's life processes. Analogous structures are features in different species that serve similar functions but evolved independently, showing convergent evolution. Homologous structures are similar in form due to shared ancestry but may serve different functions in the present. Understanding vestigial structures helps to illustrate how organisms adaptively change over time while retaining traces of their evolutionary past.