What is the integumentary system of a worm?

The integumentary system of a worm primarily consists of its skin, which is a thin, moist layer that serves as a protective barrier and facilitates gas exchange through cutaneous respiration. This system also includes the underlying muscles and connective tissues, enabling movement and flexibility. The skin secretes mucus to help prevent desiccation and assist in locomotion through soil. Additionally, the integument contains sensory receptors that allow the worm to respond to its environment.