Which organ system covers the external surface of the body, but not the internal surface of the mouth?

Question

Quizplus · Accepted Answer

The integumentary system, which includes the skin, nails, and hair, covers the external surface of the body. However, it does not cover the internal surface of the mouth, which is lined by the mucous membranes of the digestive system. The other options are not related to the covering of the body surface.

Which Organ System Covers the External Surface of the Body