Cells & Structures of Nervous System pt.1 Flashcards
Try your best to memorize everything
Describe Neurons
Most important part of the nervous system
What are glial cells and what do they do
cells that protect the nervous system
helps w/ info processing
What is the Neuron Doctrine?
Brain is composed of independent cells
Info is transmitted from cell to cell in tiny gaps called synapses
What are the 4 Neuron function zones?
- Input zone: receives info through dendrites
- Integration zone: integrates info it receives
- Conduction zone: conducts output info away from
cell body - Output zone: axons at bottom communicate
activity to other cells
What is an Axon Hillock?
cone-shaped area of the cell body that lets axon rise - converts input into electrical signals that travel down axon and innervate target cells
Spot of neural integration
What is an Axon Collateral?
a branch of an axon that also ends in terminals
What is a Motor Neuron? Describe it.
Cells in brain that stimulate muscles; large and long axons
What is a Sensory Neuron? Describe it.
various shaped nerve cells that respond to environmental stimuli (5 senses)
What are Interneurons? Describe it.
connector between sensory and motor neurons & has tiny axons
analyzes input fom one set of neurons and communicates it with others
Describe multipolar neurons
1 axon, many dendrites (most common)
Describe Bipolar Neurons
one axon one dendrite
Describe Unipolar Neurons
A single extension brances in 2 directions forming an input and output zone
What are the 3 synapse components?
Presynaptic membrane
postsynaptic membrane
Synaptic cleft
What are synaptic vescicles?
small spheres in presynaptic axon terminals that contain a neurotransmitter
What do Neurotransmitters receptors do?
In postsynaptic membrane are specialized proteins that react to neurotransmitter molecules
What is neural plasticity?
refers to the continual remodeling of neural connections
What do oligodendrocytes do?
Glial cells that form a myelin sheath in brain and spinal cord
What are Schwann cells?
Glial cells that provide myelin sheaths to neurons outside brain and spinal cord
What are the nodes on ranvier?
gaps between sections of myelin where axon is exposed
What are astrocytes?
star-shaped cells that go around & between axons, secretes chemicals, form outer membrane of brain
What are Microglial cells?
tiny mobile cells that remove debris from injured/dead cells
How do glial cells respond to injury?
by swelling, damages neurons
