Science: Nervous System

• Divisions of the nervous system

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

  • Brain
  • Spinal Cord
• Divisions of Peripheral Nervous System (PNS)

  • Somatic nervous system
  • Autonomic nervous system
• Components of Peripheral Nervous System (PNS)

  • Cranial nerves
  • Spinal Nerves
• Neuron or nerve cells


  The basic unit of communication
• Neuron


  The basic functional units
• Cell body


  • Contains nucleus, cytoplasm and organelles
• Dendrites


  Receives and carries information toward the cell body
• Axon


  A long tail-like fiber that extends from the cell body and carries messages away from the cell body
• Myelin Sheath


  Covers the axon and speeds up the travel of the nerve impulse
• Axon Terminal


  Passes the message to the next dendrites
• Synapse


  A small gap at the end of a neuron that allows a signal to pass from one neuron to the next
• Sensory Neuron


  Receives initial stimuli from the sense of organs
• Interneuron


  Connects both sensory neuron and motor neuron
• Motor Neuron


  Receives a message from the brain and spinal cord and sends it to the muscles or glands
• Brain


  The important and delicate organ
• Cerebrum


  • The largest region and most noticeable part
• Cerebellum


  • The second largest part, and it is located behind the brain
• Brain stem


  Connects the spinal cord to the rest of the brain
• Spinal cord


  A thick bundle of nerve fibers, and it relays on nerve impulse to and from the brain
• Spinal column/Spine/Backbone


  Protects the spinal cord
• Hemispheres of the cerebrum

  • Right
  • Left
• Right side of the brain

  Controls left side
• Left side of the brain

  Controls right side
• Skull


  The bone that protects the brain
• Meninges


  The 3 thin layers of tissue that protect the brain
• Cerebrospinal Fluid (CSF)


  The colorless fluid
• Parietal Lobe


  Controls the sense of touch, taste, and smell, and controls solving math calculations and academic skills
• Occipital Lobe


  Controls reading and visual interpretation
• Temporal Lobe


  Controls memory, hearing, feelings, and musical awareness
• Frontal Lobe


  Controls problem solving, Judgement, reasoning, and voluntary movement
• Cranium


  The bone that protects the grain
• Cerebral cortex


  The surface of the brain
• Corpus callosum


  Connects the right and left hemispheres
• Pons


  Connects the cerebrum with the cerebellum
• Medulla Oblongata


  Controls involuntary actions such as heartbeat, breathing, and blood pressure
• Pituitary Gland


  A gland attached at the base of the brain that secretes hormones
• Thalamus


  Serves as the relay station
• Hypothalamus


  Monitors internal condition to keep your body in a stable state