Receptors. Receptors are groups of specialised cells. They can detect changes (stimuli) in the environment. Receptors are often located in the sense organs, such as the ear, eye and skin.Each organ has receptors sensitive to particular kinds of stimulus. The table shows some receptors and the stimuli they detect.he sense organs contain receptors that are sensitive to stimuli. The nervous system consists of the central nervous system-brain and spinal cord-and peripheral nerves. Nerve impulses travel through the axons of neurones-nerve cells.