1. Nervous tissue nervous system overview NS organization terminology anatomy of a neuron neuroglial cells myelin sheath synapse anatomy

2. An overview of the nervous system

3. PNS CNS Sensory Motor VisceralSomatic SympatheticParasympathetic CNS = brain and SC PNS = everything else Nervous system divisions

4. 1 3 2 Peripheral NS Central NS Muscles 1 = sensory (afferent) neuron 2 = interneuron (CNS) 3 = motor (efferent) neuron Somatic Nervous System

5. 1 3 2 Visceral Nervous System 1 = sensory neuron 2 = interneuron (CNS) 3 = motor neuron Peripheral NSCentral NS

6. Nucleus Axons or Dendrites Cell body Neuroglial cells Nervous system = neurons and glia

7. Typical neuron dendrites Axon hillock axon Myelin sheath Terminal Arborizations with synaptic knobs

8. Blue = axon Multipolar Neurons bipolar Unipolar or pseudounipolar

9. Neuroglia CNS – Astrocytes (green) – Microglia (purple) – Oligodendrocytes (blue) – Ependymal (pink) PNS – Schwann – Satellite cell

10. Neuroglia can undergo mitosis (for better or worse) gliomas (ependymoma, astrocytoma, oligodendroglioma)

11. Formation of the myelin sheath - PNS Schwann cell neurilemma Myelin sheath

12. Fig. 13.7a(TE Art) Oligodendrocyte Nerve fiber Myelin Myelin sheath in the CNS

13. CNS PNS oligodendrocyte Schwann cell Schwann cell helps damaged nerve fibers grow back to target Oligodendrocyte does not Nerve regeneration in PNS not CNS

14. axons S

15. Multiple sclerosis myelin sheath in CNS deteriorates replaced by scar tissue Symptoms? Signs?

16. Postsynaptic neuron Synaptic vesicles Synaptic cleft Neurotransmitter receptor Presynaptic neuron Synapses Neurotransmitters chemical signals

17. Synaptic vesicles containing ACh (acetylcholine) Motor end plate Neurotoxins: botulism, curare, tetanus toxin Neuromuscular junction AChE – breaks down ACh Excitatory NT’s Glutamate – brain Aspartate – SC Inhibitory NT’s GABA – brain Glycine - SC