Neuron Anatomy

Nervous system functions

• sensory

• integration

• motor

Tract

bundle of axons in the CBS

Nerve

bundle of axons in the PNS

Nucleus

cluster of neuronal cell bodies found in the CNS

ganglion

cluster of neuronal somas in PNS

Gray matter

unmyelinated axons, neuronal cell bodies, dendrites, axon terminals, supporting neuroglia, and blood vessels

white matter

myelinated axons and blood vessels

Unipolar neuron

mostly sensory

bipolar neuron

rare usually special senses

multipolar

most common

types of glial cells in the CNS

Astrocytes

Microglia

Ependymal

Oligodendrocytes

types of glial cells in the PNS

satellite cells

schwann cells

Integration

sensory info is processed y the brain and higher regions of the spinal cord for appropriate responses to be initiated

Sensory

Various external and internal stimuli such as touch and increased blood pressure

Motor

impulses that generate a response in an effector organ

Somatic nervous system

the subdivision of the nervous system involves motor responses that are voluntary or conscious in nature

autonomic

subdivision of the nervous system made of sympathetic and parasympathetic nervous system. involuntary motor responses.

enteric nervous system

often called the brain of the gut involves involuntary responses of the GI tract.

draw and label a neuron

should include

• myelin sheath

• axon

• axon hillock

• soma/body

• dendrites

• axon terminals

• gap junctions

astrocyte

• most abundant and largest of the neuroglial cells in the CNS

• maintain the blood brain barrier

• provide structural support to the CNS

Oligodendrocytes

• found in the CNS

• produce the myelin sheath around axons

Ependymal cells

• found in CNS

• Lines ventricles of the brain and central canal of the spinal cord

• play an important role in secretion and monitoring of cerebrospinal fluid

microglial cells

• smallest found in the CNS

• serve a protective role in the CNS where they remove cellular debris

• think immune system of CNS

Satellite cells

• provide structural support and forms a barrier that regulates the exchange of substances between neuronal bodies and surrounding interstitial fluid in the PNS

Schwann cells

produce the myelin sheath of the PNS

Ligand Gated channels

• ligand binds

• channels open

• alters membrane potential

voltage gated

• voltage changes activating VG channels changing in membrane potential

leak channels

open continuously

mechanically gated

transmembrane proteins that open or close in response to physical deformation or mechanical stress on the cell membrane,

Draw the nervous system organization