What components are included in the integumentary system?

The integumentary system is primarily responsible for protecting the body and maintaining homeostasis. It includes the skin as the main component, which is vital for barrier functions, sensory perception, and temperature regulation. In addition to skin, this system encompasses various structures like scales in reptiles and feathers in birds. These components also contribute to the protective features of the integument, aiding in thermoregulation and serving as a defense against environmental hazards.

The other options refer to systems that serve entirely different functions. The heart and blood vessels are part of the cardiovascular system, focusing on circulation. The mouth and digestive organs belong to the digestive system, which processes food and extracts nutrients. Kidneys and reproductive organs are components of the urinary and reproductive systems, respectively, focused on waste removal and reproduction. Each of these systems functions independently from the integumentary system, emphasizing that the correct components associated with the integumentary system are indeed skin, scales, and feathers.