Neurons

• WHAT IS A NEURON?

  SPECIALISED CELLS THAT TRANSMIT ELECTRICAL IMPULSES. THEY FORM THE BASIC UNIT OF THE NERVOUS SYSTEM AND ALLOW DIFFERENT PARTS OF THE BODY TO COMMUNICATE
• WHAT IS AN ACTION POTENTIAL?

  THE CHANGE IN ELECTRICAL POTENTIAL ALONG THE AXON OF A NEURON DURING TRANSMISSION OR CONTRACTION
• WHAT IS THE RESTING STATE OF A NEURON AND WHAT DOES IT CHANGE TO DUE TO AN AP?


  -70MV TO +40MV (1MS)
• WHAT ARE THE TYPES OF NEURONS?

  SENSORY

  RELAY

  MOTOR
• SENSORY NEURON


  CARRIES MESSAGES FROM THE PNS TO THE CNS. THEY HAVE LONG DENDRITES AND SHORT AXONS
• RELAY NEURON


  CONNECTS THE SENSORY NEURONS TO THE MOTOR OR OTHER RELAY NEURONS. THEY HAVE SHORT DENDRITES AND LONG AXONS.
• MOTOR NEURON


  CONNECTS THE CNS TO EFFECTORS SUCH AS MUSCLES AND GLANDS. THEY HAVE SHORT DENDRITES AND LONG AXONS.
• WHAT IS A REFLEX AN GIVE AN EXAMPLE


  AN INVOLUNTARY MOVEMENT EG KNEE JERK