Guide cells to their proper position during development
Oligodendrocytes and Schwann cells
Insulate axons to increase the speed of action potential conduction
Removing debris
Microglia remove debris after injury or neuronal death
Neuron Doctrine
Brain is composed of independent cells
Sensory (afferent)
Carries sensory input
Interneurons
Refers to any neurons that is not a sensory or motor neuron
Motor (efferent)
Carries comands to muscles
Neurons can be classified
Function
Projection neurons
Projects outside of the structure within which they reside
local interneurons
Projects only within the structure within they reside
Axon
Arises from the axon hilllock
Cell body
Metabolic center
Neucleus
Endoplasmix reticulum,
Cajal proposed
Principle of dynamic polarization, which states that the signals within a neuron flow in one direction
Synaptic vesicles
small spheres in presynaptic axon terminals that contain a neurotransmitter
Neurotramitters
Specialized chemical substance
Receptors
Specialized proteins that react to a neurotransmitter
Dendritic spines
Studded on the dendrites and increase surface are
The property of neural plasticity
Dendritic spines allow their number and structure to be rapidly altered by experience
Axon hillock
Cone shaped area of the cell body that gives rise to the axon
Axon collateral
Branch of an axon that also ends in terminals and innervates other cells
Axon transport
Movement of materials within an axon
How many axons emerge from a neuron cell body
1
2
Many
Which has a larger diameter
Densities
Cajal's principle of connections specificity
Each cell makes a specific connection at particular points with specific target cells and not others
Paul weiss
Proposed nervous system was a "vast neural network that connects the sense organs and muscles to the brain originates as an undifferentiated and unspecified mesh of randomly connected nerve fibers
Roger sorrry
Found severed, thousands of individuals fibers that make up each optic nerve grow back into the brain