Nervous system

• What is an action potential (AP)?

  A sequence of rapidly occurring events
• What happens during depolarization in an action potential?

  The membrane potential decreases and reverses
• What is the role of voltage-gated Na+ and K+ channels during an action potential?

  They open in sequence during the AP
• What does the all-or-none principle state about action potentials?

  If threshold is reached, the AP is the same
• How does a stronger stimulus affect the action potential?

  A stronger stimulus does not increase impulse size
• What are the steps of neurotransmission?

  1. AP reaches axon terminal
  2. Ca2+ enters synaptic knob
  3. Neurotransmitter released by exocytosis
  4. Neurotransmitter binds to receptors on postsynaptic neuron
  5. Binding opens specific channels
• What are the three layers of spinal meninges?

  Dura mater, arachnoid mater, pia mater
• What is the function of the epidural space?

  It is between vertebrae and dura mater
• What is the role of cerebrospinal fluid (CSF)?

  It cushions the brain and provides nutrients
• What are the functions of the spinal cord?

  • Reflexes: fast, involuntary actions
  • Simple reflexes: withdrawal
  • Complex reflexes: learned sequences
• What are the steps of a reflex arc?

  1. Sensory receptor responds to stimulus
  2. Sensory neuron transmits signal to spinal cord
  3. Integrating center processes signal
  4. Motor neuron sends response signal
  5. Effector (muscle) responds
• What is the role of the medulla oblongata?

  Regulates heart rate and blood pressure
• What connects the medulla to the midbrain?

  Pons
• What is the function of the reticular activating system (RAS)?

  Helps maintain consciousness and induce sleep
• What are the functions of the cerebellum?

  Balance, muscle tone, coordination
• What does the thalamus do?

  Major sensory relay center
• What is the role of the hypothalamus?

  Controls pituitary and hormone production
• What does the pineal gland secrete?

  Melatonin
• What are the functions of the cerebrum?

  • Sensory perception
  • Voluntary movement control
  • Language and complex mental events
  • Divided into right and left hemispheres
• What are the four major lobes of the cerebral cortex?

  Occipital, temporal, parietal, frontal
• What is the role of the limbic system?

  Emotion and basic behavioral patterns
• What is lateralization in the brain?

  Each hemisphere controls opposite body side
• What is the role of the left hemisphere?

  Spoken and written language skills
• What is the role of the right hemisphere?

  Spatial and pattern recognition
• What is memory?

  Process for storing and retrieving information
• What are the cranial nerves and their functions?

  1. Olfactory: smell
  2. Optic: vision
  3. Oculomotor: eye movements
  4. Trochlear: eye movements
  5. Trigeminal: face sensation and chewing
  6. Abducens: eye movements
  7. Facial: facial expression and taste
  8. Vestibulocochlear: hearing
  9. Glossopharyngeal: taste and swallowing
  10. Vagus: major parasympathetic nerve
  11. Accessory: head and shoulder movement
  12. Hypoglossal: tongue movement
• What happens to the brain during aging?

  Decline in brain mass and function
• What causes rapid brain growth in early life?

  Increase in neuron size and neuroglia
• What is the effect of aging on synaptic contacts?

  Fewer synaptic contacts with aging