字幕列表 影片播放 列印英文字幕 The integumentary system, is made up of the skin, hair and fingernails. The integumentary system particularly the skin, has a number of functions. Your skin protects you from germs, foreign materials and from drying out. Your skin also plays a role in excretion, getting rid of urea and salts when you sweat. Your skin helps to regulate your body temperature by dilating and constricting blood vessels, to control heat exchange with the environment. Nerve endings in your skin , give you your sense of touch and allow you to detect heat, pressure or pain. The outer most layer of skin, is called the epidermis. Just below the epidermis, is the second layer of skin called the dermis. The dermis contains most of the important structures of the skin like nerves that help you send stimuli, blood vessels, sweat glands, oil or sebaceous glands and hair follicles. The arrector pili muscle, makes our hair stand on end and gives us goose bumps. The third, and deepest layer of our skin is the subcutaneous layer. Adipose, or fat tissue, is stored in the subcutaneous layer and helps to keep your body insulated. The skin is the largest organ in the body, and performs many functions that help to maintain your health. The integumentary system therefor is critical to your survival.