.3 Reflex

• rapid reaction under one second

  automatic and involuntary

  cannot stop it

  short-lived

  don’t require conscious thought
• Controlled by a simple neurone pathway, localised in the part of the body where the reflex occurs Starts with the receptor, detects the stimuli/change in stimuli to respond to, turns a physical change into an electrical signal

  Passed onto the sensory neurone Carries the signal into the spinal cord where it reaches a co-ordinator

  A co-ordinator is an intermediate neurone that carries a signal to a motor neurone Brings signal to effector e.g muscle
• Reflex

  rapid reaction under one second

  automatic and involuntary

  cannot stop it

  short-lived

  don’t require conscious thought
• Controlled by a simple neurone pathway, localised in the part of the body where the reflex occurs

  Starts with the receptor, detects the stimuli/change in stimuli to respond to, turns a physical change into an electrical signal
• Passed onto the sensory neurone Carries the signal into the spinal cord where it reaches a co-ordinator

  A co-ordinator is an intermediate neurone that carries a signal to a motor neurone Brings signal to effector e.g muscle
• Very localised in the part of the body where they occur

  Response can be rapid so signals don’t need to travel to the brain and back

  prevents harm/damage occurring to the body
• Doesn’t involve many synapses >which are slow to transmit information across neurones
• Effective in protecting the body from harm Some signals go to the brain >allowing the brain to override the response if its comprehensive decision making process deems it necessary
• Simplicity of a reflex means that it doesn’t need to be learnt and is effective from birth e.g grab reflex