Receptors are the sensory structures which provide information about the external environment to the body. This helps the brain to instruct a related organ to take the required action. Receptors are very important for our survival. For example, if a person is blind, performing certain ordinary task may be very difficult for him. Since, one of the receptors (eyes) are not functional in his body, he may not be able to see the obstruction in his path or may even fall in a pit.