Integumentary system: it is the most extensive system of the human body since it covers it completely. Its main functions are to separate, protect, and inform our body of the environment that surrounds us. Among its many functions are: It is the first immunological barrier that protects us from the external environment; It intervenes in avoiding drying out.Excresion: Through sweating waste is excreted and body temperature is reduced.Diagnostic Role: skin can present the symptoms of many diseases, which makes it possible to diagnose them.