| The body has several senses that allow it to perceive its surroundings. The five basic senses are sight, sound, touch, taste, and smell. Other external senses include pain, temperature, position, and movement. Although we can selectively perceive the information received through our external senses, we are typically unaware of our internal senses. These senses are involved in the detection and regulation of internal functions of the body. Blood pressure and serum CO2 (carbon dioxide) levels are two examples of the many internal states monitored by the body. If an external sense is absent or limited, other senses may improve to compensate for the lack elsewhere. A blind person may develop acute hearing and more sensitive touch. When a limited sense restricts daily activity, it is considered a disability. |