Which organ has two atria and one ventricle in amphibians?

Which organ has two atria and one ventricle in amphibians?

• A. Lungs
• B. Stomach
• C. Heart
• D. Kidneys

Answer: (C)

In amphibians the heart is three-chambered, with two atria and one ventricle. The two atria receive blood from separate circulatory routes—the right atrium tends to collect deoxygenated blood returning from the body, while the left atrium collects oxygenated blood from the lungs and skin. Those bloods mix in the single ventricle before being pumped out to the rest of the body and the lungs. This arrangement is characteristic of amphibians and different from other organs listed, which do not contain chambers like atria and a ventricle. The lungs are respiratory organs, the stomach is part of digestion, and the kidneys filter blood, none of which have this atrial-ventricular structure.

In amphibians the heart is three-chambered, with two atria and one ventricle. The two atria receive blood from separate circulatory routes—the right atrium tends to collect deoxygenated blood returning from the body, while the left atrium collects oxygenated blood from the lungs and skin. Those bloods mix in the single ventricle before being pumped out to the rest of the body and the lungs. This arrangement is characteristic of amphibians and different from other organs listed, which do not contain chambers like atria and a ventricle. The lungs are respiratory organs, the stomach is part of digestion, and the kidneys filter blood, none of which have this atrial-ventricular structure.