The Neuron

The NeuronDendritesCell body (perikaryon, soma)

Support cells (neuroglia)- more abundant than neurons- more mitotic capability

Axon hillock

Gaps between Schwann cells called nodes of Ranvier

axolemma

Myelinated axons: sheath of Schwann and myelin sheathone Schwann cell myelinates a single axonmultiple Schwann cells needed to cover entire length of an axon

Oligodendrocytes myelinate CNS axons (if myelinated)

Central Nervous System1. brain2. spinal cord

- ganglia associated

3. axons project to and from the body (CNS PNS)4. cell bodies in CNS except some in ganglia

Transmission1. innervation

- cell body as integrator2. action potentials (impulses)

- axon hillock3. myelin sheath

Synapses- presynaptic terminal- postsynaptic terminal- neurotransmitters- ligand-gated ions channels on postsynaptic membrane

Gap junction (nexus)- is an electrical synapse

Nervous System

Organization of neurons1. circuits for stimulus-response2. exchange of information

Neuron signaling1. afferent vs. efferent2. interneurons3. circuits

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Anencephaly





Spina bifida occulta with meningocoele





Spina bifida with failure of neuropore closure



Cortical dysplasia

The Neuron

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Transcript of The Neuron