Brain Basics Flashcards
Brain is composed of
neurons, glia, stem cells, blood vessels
Brain Cells are not
Replaced. No adult neurogenesis.
Humans have the highest brain
neuron density
The neuron is composed of
Dendrite -> soma -> axon -> terminals
Pyramidal shaped neuron
Has apical and basal long dendrites.
Stellate shaped neuron
Neuron with star like shape. Dendrites in all directions
Purkinje shaped neuron
Very thin dendrites in a dense configuration, like roots.
Projection neurons (Shape, function)
Long axon. Projects from one brain area to another brain area.
Example: Medium spiny projection neurons (MSNs) 96% of neurons
Interneurons (Shape, function)
Star shaped. Axons project locally. Modify the signals. Often inhibitory in nature. Can synchronize the activity of projection neurons. Can gate information.
Glial Cells - Microglia
It spots problems and “hunts it”, they engulf the problem. (Like the immune system of your brain.)
Glial Cells - Astrocytes
The most abundant.
Regulates the environment of synapses.
Mediates needs and how active the brain is
Glial Cells - Oligodendrocytes
Their function is to myelinate multiple axons at once in the central nervous system
Glial Cells - Schwann cells
Work in the Peripheral nervous system.
They wrap around axons of motor and sensory neurons to form the myelin sheath.
The Tripartite synapse
2 neurons and 1 glial cell wrapped around the synaptic site
Astrocyte in Tripartite synapse
Astrocytes release signals in synapse, shaping conditions. Helps with cleaning of NTs. They release D-serine.
D-serine
Astrocytes release this to the site to manipulate ???
glutamatergic contribution to central chemoreception
D-Serine activates glutamate receptors that are involved in the formation of new synapses, which are important for learning and memory
Gray matter
Cell bodies of the neurons and unmyelinated neurons (like interneurons)
White matter
Myelinated axons
Anatomical dimensions
Anterior and posterior
Front and back (brain) up and down (spine)
(in most animals it is just front and back)
Varies on a Z-axis