Nervous system

• Divisions of the Nervous System

  • Central Nervous System (CNS)
  • Peripheral Nervous System (PNS)
• Central Nervous System (CNS)


  • Brain
  • Spinal cord
• Peripheral Nervous System (PNS)


  • Nerves and spinal nerves connecting the CNS to the rest of the body
• Cells of the Nervous System

  • Sensory neurones
  • Relay neurones
  • Motor neurones
• Divisions of the Peripheral Nervous System

  • Efferent nerves (nerves out of CNS)
  • Afferent nerves (nerves into CNS)
  • Motor division
  • Sensory division
  • Autonomic nervous system
  • Somatic nervous system
  • Sympathetic nervous system
  • Parasympathetic nervous system
• Brain


  • Control center of the body
  • Divided into 3 parts: cerebrum, cerebellum, brain stem
  • Made up of more than 10 billion nerve cells
  • Protected by the skull
• Spinal Cord


  • Connects the brain to the rest of the nervous system
  • Sends messages to the brain
  • Protected by a column of bones, the vertebra
  • Produces some behaviors of its own without the brain's help (spinal reflexes)
• Regions of the Spinal Cord

  • Cervical region
  • Thoracic region
  • Lumbar region
  • Sacral region
• Central Nervous System (CNS)


  Brain and spinal cord
• Peripheral Nervous System (PNS)


  Nerves and spinal nerves connecting the CNS to the rest of the body
• Divisions of the Peripheral Nervous System

  • Sensory (afferent) division
  • Motor (efferent) division
  • Sympathetic division
  • Parasympathetic division
  • Somatic nervous system
• Sensory (afferent) division


  • Conducts impulses from receptors to the CNS
• Motor (efferent) division


  • Conducts impulses from the CNS to muscles and organs
• Sympathetic division


  • Responsible for "fight or flight" response
• Parasympathetic division


  • Responsible for "rest and digest" functions
• Somatic nervous system


  • Responsible for voluntary control of skeletal muscles
• Types of Neurons


  • Sensory neuron
  • Motor neuron
  • Relay neuron
• Sensory neuron


  Carries information from sensory receptors to the CNS
• Motor neuron


  Carries information from the CNS to muscles and organs
• Relay neuron


  Connects sensory and motor neurons within the CNS
• Sensory input


  • Integration in the CNS
  • Motor output
• Functions of the Nervous System

  • Relay messages
  • Process information
  • Analyze information
• Regions of the Brain

  • Frontal lobe
  • Parietal lobe
  • Temporal lobe
  • Occipital lobe
  • Cerebellum
  • Brain stem
• Frontal lobe


  Responsible for thinking, memory, behaviour and movement
• Parietal lobe


  Responsible for language and touch
• Temporal lobe


  Responsible for hearing, learning and feelings
• Occipital lobe


  Responsible for vision
• Cerebellum


  Responsible for balance and coordination
• Brain stem


  Regulates basic body functions like heart rate, breathing and temperature
• The spinal cord can produce some behaviors on its own without the brain's help (spinal reflexes)
• Regions of the Spinal Cord

  • Cervical region
  • Thoracic region
  • Lumbar region
  • Sacral region
• Cervical region


  Supplies the back of the head, neck, shoulders, arms, hands and diaphragm
• Thoracic region


  Supplies the chest and some parts of the abdomen
• Lumbar region


  Supplies the lower back, thighs and legs
• Sacral region


  Supplies the buttocks, legs, feet, anal and genital area
• Divisions of the Peripheral Nervous System

  • Sensory (afferent) division
  • Motor (efferent) division
  • Autonomic nervous system
• Sensory (afferent) division


  Conducts impulses from sensory receptors to the CNS
• Motor (efferent) division


  Conducts impulses from the CNS to muscles and organs
• Autonomic nervous system


  Controls involuntary functions like heart rate, breathing, digestion
• Divisions of the Autonomic Nervous System

  • Sympathetic division
  • Parasympathetic division