Which of the following best describes metamorphosis in amphibians?

• A. Metamorphosis is the growth of bones from cartilage.
• B. Metamorphosis is the process of aging.
• C. Metamorphosis is the transition from larval forms with gills to adult forms with lungs.
• D. Metamorphosis is the migration to different habitats.

Answer: (C)

Metamorphosis is a major reorganization of an animal’s body plan during development. In amphibians, it means changing from an aquatic larval form that has gills, a tail, and no legs to an adult form with legs, lungs, and a different set of organs. This transformation is largely controlled by thyroid hormone and is triggered as the animal approaches adulthood, involving widespread changes to the digestive and circulatory systems, among others. It’s not simply growing bones, aging, or migrating to a new habitat; it’s a complete developmental remodeling to fit a different lifestyle.