NOT FINISHED -stimuli and receptors

• stimulus - change in the internal or external environment
• effectors - cells that bring about a response to a stimulus, to produce an effect and includes muscle cells and cells found in the glands
• sensory neurone - transmit electrical impulses from receptors to the central nervous system - the bran and the spinal cord
• motor neurone - transmit electrical impulses from the central nervous system to effectors
• relay neurone - transmit electrical impulses between the sensory neurone and motor neurone
• add the labels

  A) stimulus

  B) receptors

  C) sensory

  D) central nervous system

  E) effectors

  F) motor

  G) response

  
• the peripheral nervous system - made up of neurones that connect the central nervous system to the rest of the body
• somatic nervous system - controls conscience activities e.g. running offers the 'flight or fight ' response
• the autonomic nervous system - controls unconscious activities e.g. digestion
• reflex - where the body responds to stimulus without making a conscious decision so information can travel really fast from receptor to effector
• reflex arc - the pathway of neurones linking receptors to effectors and is made up of three neurones: sensory, a relay and a motor neurone