Skin

The integumentary system is a very important system for the human body. It is the largest of the body’s organs consisting of about 12% to 15% of the total body weight. It protects the body from injury, infection, dehydration and receives sensory input from the body’s external environment. This system acts as a cushion to protect the deep tissues and organs within our body. Sebaceous glands in the skin are oil gland that will secrete an oily fluid that moistens and softens hair. A sweat gland regulates body temperature and protects against bacteria. It helps to excrete wastes by perspiration, and uses sensory receptors to detect pain. It regulates the body from abrupt changes in the temperature, sensations, and pressure. The blood supply gives nutrients to the epidermis and dermis, and facilitates heat loss when the body is too hot or too cold. Sensory nerve endings detect the heat, cold, light touch, deep pressure, and vibrations. The integumentary system guards the body from infectious organisms, sunburn, and generates vitamin D. Included in this system is the ability to store water, fat, and glucose. Smooth muscle helps to contract when the person gets freighted or cold. Skin aids in the formation of new cells to repair small injuries and aids changes to the skin color which can indicate illness or medical conditions. The skin has melanocytes which creates a dark pigment called melanin. This protects the body from the sun’s rays and causes people to suntan. Keratinocytes are a tough, waterproof protein called keratin that protects living cells below the skin and rapid replacement of these cells allow the skin to heal quickly after an injury. Adipose tissue is fat storage in the skin that provides insulation. The skin helps to maintain homeostasis by negative feedback. Negative feedback has two areas that help to maintain homeostasis and they are controlled variable which is physical or chemical property that must be controlled and sensors that sends information to the control center. The activity of the cells, tissues, organs, and organ systems are carefully watched to keep changes to the body within acceptable limits.