Sensory receptors

• what is a sensory receptor?

  Specialised cells that can detect changes in the surroundings, most are energy transducers that convert one form of energy to another.
• each type of transducer is adapted to detect changes in a particular f orm of energy. This may be a change in light levels, a change in pressure on the skin etc.
• What is a stimulus?

  a change in the environment, be it a change in the energy level, or the presence of a new chemical. Whatever the stimulus, the sensory receptors respond by creating a signal in the form of electrical energy called a nerve impulse.
• if there is a change in light intensity, what is the sensory receptor?


  Light sensitive cells, rods and cones, in the retina
• What is the energy change if there is a change in light intensity?


  Light to electrical
• What sensory receptor is required when there is a change in temperature?

  Temperature receptors in the skin and hypothalamus
• What is the energy change involved if there is a change in temperature?


  Heat to electrical
• What is the sensory receptor for a change in pressure on the skin?


  Pacinian corpuscles in the skin
• What is the energy change involved if there is a change in pressure on the skin?


  Movement to electrical energy
• What is the sensory receptor if there is a change in sound?


  Vibration receptors in the cochlea of the energy.
• What is the energy change if there is a change in sound?


  Movement to electrical
• What is the sensory receptor involved if there is a change in length of muscle?


  Muscle spindles in skeletal muscles
• What is the energy change if there is a change in movement?

  Movement to electrical
• What is the sensory receptor if there is a change in the chemicals in the air?

  Olfactory cells in the epithelium lining the nose
• What is the sensory receptor if there is a change in the chemicals in the food one consumes?

  Chemical receptors in the tastebuds on the tongue
• what is the pacinian corpuscle?


  A pressure sensor that detects changes in pressure on the skin
• Describe the structure of the Pacinian corpuscle?


  The corpuscle is an oval shaped structure that consists of a series of concentric rings of connective tissues wrapped around the end of a nerve cell. when pressure on the skin changes, this deforms the rings of connective tissue that pushes against the nerve ending. The courpuscle is sensitive only to changes in pressure that deform the rings of connective tissue.