What is metamorphosis in amphibians?

What is metamorphosis in amphibians?

• A. The growth of bones from cartilage.
• B. The process by which amphibians transition from larval forms with gills to adult forms with lungs, often involving habitat changes.
• C. A simple color change.
• D. A seasonal migration.

Answer: (B)

Metamorphosis in amphibians is the major developmental change that shifts an animal from an aquatic larval form to an adult form adapted to different conditions. In many amphibians, eggs hatch into tadpoles that have gills, a tail, and live in water. Through metamorphosis, they develop legs, lose or reduce their gills, and form lungs to breathe air, often accompanying a move from water to land. Hormonal signals, especially thyroid hormones, drive these dramatic changes, reorganizing organs and behavior for the adult lifestyle. This is why the description of transitioning from larval forms with gills to adult forms with lungs, often with habitat changes, is the best answer. The other options describe separate processes—bone formation, simple color change, or seasonal migration—that aren’t the same transformative shift Amphibians undergo.

Metamorphosis in amphibians is the major developmental change that shifts an animal from an aquatic larval form to an adult form adapted to different conditions. In many amphibians, eggs hatch into tadpoles that have gills, a tail, and live in water. Through metamorphosis, they develop legs, lose or reduce their gills, and form lungs to breathe air, often accompanying a move from water to land. Hormonal signals, especially thyroid hormones, drive these dramatic changes, reorganizing organs and behavior for the adult lifestyle. This is why the description of transitioning from larval forms with gills to adult forms with lungs, often with habitat changes, is the best answer. The other options describe separate processes—bone formation, simple color change, or seasonal migration—that aren’t the same transformative shift Amphibians undergo.