Question

A frog must swallow air to expand its lungs because the frog

• A. Has no diaphragm
• B. Has no vagus nerve
• C. Is a relatively primitive vertebrate
• D. Do not breathe though its skin

Answer 1

The correct option is A Has no diaphragm

Humans breathe exclusively through their lungs, but frogs utilise their lungs for only a part of their respiration. Frog lungs have thin walls and are sac-like. They do use their lungs as a buoyancy device when swimming. It lacks diaphragm so they are unable to change to expand and change the capacity of the lungs. So, the correct answer is option A.