The tegumentary system serves several functions, beginning with protection. The skin protects against environmental effects, mechanical impacts, temperature changes, radiation, and microorganisms. It also serves to contain tissues, organs, and fluids to prevent dehydration, regulates thermal stability, plays an essential role in sensory perception, and produces Vitamin D. The skin consists of two layers, the epidermis and dermis, both with different functions and structures. The epidermis produces keratin and provides protection against the environment, while the dermis contains collagen and elastic fibers responsible for the skin's strength and tone. The subcutaneous tissue stores fat and the skin's appendages, such as hair follicles, play an essential role in the skin's function. The speaker explains the structures associated with hair follicles and their function, importance of lines of tension, and the role of the ligamentos cutáneos in determining the mobility of the skin.