Which body part is the largest organ by surface area?

Which body part is the largest organ by surface area?

• A. Liver
• B. Heart
• C. Lungs
• D. Skin

Answer: (D)

Skin covers the entire exterior of the body, forming the largest continuous surface area. In an average adult, it spans about 1.6 to 2 square meters, which is bigger than any other single organ’s external surface. This vast area enables essential roles like protection, temperature regulation, and sensation. Other organs like the liver and lungs are large, but they are internal and their functions rely on internal surface features rather than the body's outer boundary.

Skin covers the entire exterior of the body, forming the largest continuous surface area. In an average adult, it spans about 1.6 to 2 square meters, which is bigger than any other single organ’s external surface. This vast area enables essential roles like protection, temperature regulation, and sensation. Other organs like the liver and lungs are large, but they are internal and their functions rely on internal surface features rather than the body's outer boundary.