Nerve lab

• Divisions of the nervous system

  • Sensory division (afferent)
  • Motor division (efferent)
• Sensory division (afferent)


  • Somatic
  • Visceral
• Motor division (efferent)


  • Somatic
  • Autonomic (ANS)
• Autonomic nervous system (ANS) pathways

  • Preganglionic
  • Postganglionic
• Divisions of the autonomic nervous system

  • Parasympathetic
  • Sympathetic
• Development of nerve tissue

  1. Ectoderm

  2. 3rd week of development

  3. Neural tubes give rise to CNS, neurons and glial cells
• Main types of neurons

  • Multipolar
  • Bipolar
  • Unipolar/Pseudounipolar
  • Anaxonic
• Dendrites and dendritic spines

  • Increase surface area for synaptic connections
• Glial cells of the CNS

  • Astrocytes
  • Oligodendrocytes
  • Ependymal cells
  • Microglia
• Astrocytes


  • Provide structural and metabolic support for neurons
  • Regulate extracellular ion and neurotransmitter concentrations
• Ependymal cells


  • Line the ventricles and central canal of the CNS
  • Produce and circulate cerebrospinal fluid
• Microglia


  • Immune cells of the CNS
  • Phagocytose pathogens and damaged cells
• Major structures of the central nervous system

  • Cerebrum
  • Cerebellum
  • Spinal cord
• Meninges


  • Connective tissue membranes between bone and nervous tissue
  • 3 layers: dura mater, arachnoid mater, pia mater
• Blood-brain barrier


  • Functional barrier that tightly controls passage of substances from blood into CNS tissue
  • Capillary endothelium is the main structural component
• Choroid plexus


  • Highly vascular tissue in the ventricles
  • Removes water from blood and releases it as cerebrospinal fluid
  • Provides ions for neuronal activity
  • Absorbs mechanical shocks
• Arachnoid villi


  • Main pathway for cerebrospinal fluid absorption back into venous circulation
• Main components of the peripheral nervous system

  • Cranial nerves
  • Spinal nerves
  • Ganglia
• Peripheral nerve connective tissue

  • Endoneurium surrounds axons and Schwann cells
  • Perineurium surrounds fascicles
  • Epineurium is the outermost dense irregular fibrous connective tissue
• Ganglia


  • Collections of neuron cell bodies in the PNS
• Nerve regeneration in the PNS

  • Schwann cells and endoneurial tubes guide regrowth of severed axons