Which statement best describes metamorphosis?

Which statement best describes metamorphosis?

• A. It refers only to size increase.
• B. It occurs only in mammals.
• C. It does not involve physiological changes.
• D. It is the change in form and physiology during development.

Answer: (D)

Metamorphosis is the change in form and physiology during development. It isn’t just about getting bigger; it involves a radical reshaping of the body plan and how the body's systems work. For insects, this means that a larva can become an adult with a completely different shape and lifestyle, such as a caterpillar that becomes a butterfly, with major reorganization of tissues like the digestive and sensory systems. In amphibians, tadpoles develop into frogs, gaining legs, losing tails, and shifting from gill-based aquatic life to lung-based terrestrial life. This dynamic transformation—altering both structure and function as development proceeds—is what metamorphosis describes. The other statements miss that broader change: growth alone, or changes limited to mammals, or changes without physiological remodeling, do not capture the full developmental transformation involved.

Metamorphosis is the change in form and physiology during development. It isn’t just about getting bigger; it involves a radical reshaping of the body plan and how the body's systems work. For insects, this means that a larva can become an adult with a completely different shape and lifestyle, such as a caterpillar that becomes a butterfly, with major reorganization of tissues like the digestive and sensory systems. In amphibians, tadpoles develop into frogs, gaining legs, losing tails, and shifting from gill-based aquatic life to lung-based terrestrial life. This dynamic transformation—altering both structure and function as development proceeds—is what metamorphosis describes. The other statements miss that broader change: growth alone, or changes limited to mammals, or changes without physiological remodeling, do not capture the full developmental transformation involved.