Question

In which animal is respiration done by skin?

• A. Flying fish
• B. Sea horse
• C. Frog
• D. Chameleon

Hint:

Look for the animal with thin, always moist skin that can also live and breathe underwater without gills.

Answer 1

The Correct Option is C

Step 1: Recall the meaning of skin respiration.
Skin respiration, called cutaneous respiration, is a way of exchanging oxygen and carbon dioxide directly through the moist surface of the skin, without needing to breathe air into lungs or gills for that particular gas exchange. This is only possible when the skin is thin, kept moist, and has a rich network of tiny blood vessels lying just under its surface.

Step 2: Apply this to the frog.
The frog is an amphibian, meaning it lives part of its life in water and part on land. Its skin is thin, kept moist by mucus glands, and is packed with blood capillaries close to the surface. This lets the frog absorb dissolved oxygen through its skin, especially useful underwater or during hibernation in mud, in addition to breathing through lungs and its mouth lining when active on land. Because of this, the frog is the standard textbook example of an animal that breathes through its skin.

Step 3: Rule out the other animals listed.
(A) Flying fish is a bony fish that breathes using gills, and its "flying" refers to gliding above water on enlarged fins, not to any skin based breathing.
(B) Sea horse is also a fish, and like other fish it relies on gills covered by hard bony plates, not thin moist skin, so it cannot exchange gases through its body surface.
(D) Chameleon is a reptile with thick, dry, scaly skin, which is built to prevent water loss on land and is not suited to gas exchange, so chameleons breathe only through lungs.

Step 4: Final conclusion.
Since only the frog has the thin, moist, capillary rich skin needed for cutaneous respiration among the animals listed, the correct answer is the frog.

Final Answer:
The frog respires through its moist skin in addition to its lungs, making it the correct answer.