Introduction to nervous System Flashcards
What makes up the central nervous system
Brain
Spinal Cord
What makes up the peripheral nervous system
The nerves
What are the functions of the nervous system
Controls and integrates bodily activity
Reacts to constant changes in external and internal encironments
Whats the main function of the CNS
Is the mains processing center and coordinator of all our bodys functions
What are the two cells of the nervous system
Neurons
Neurogila
What are function of Neurons
Basic unit of the nervous system
Transmit electrical impulses to one another to communicate information
What are the functions of neurogila
Non-neuronal, non-excitable cells
5x as abundant as neurons
Support for neurons
- Structural nourishment insulation pathogen clearance
What is the myelin sheath
Insulates axon to increase speed of signal
What is the difference between a multipolar motor neuron and pseudounipolar sensory neuron
Motor neurons send singals from the CNS to target organs where sensory neurons bring signals from the periphery to the CNS
What is an axon
Transmits action potential
What is the trigger zone
Axon hillock; where signals summate to reach threshold and cause an action potential
What are dendrites
Collecting information from other neurons or cells
Neuron synapses on a dendrite
What are axon terminals
Where synpase occurs with next neurons in the chain or target organ
What is the central process
Part of axon proximal to the cell body
What are the peripheral process
Part of the axon distal to the cell body
Are there dendrites around the cell body in a pseudounipolar sensory neuron
No
What is a ganglion
Collection of cell bodies from multiple neurons within a nerve
What is the difference between the two type of neuroglia oligodendrocyte and schwann cell
Oligodendrocyte forms several mylein sheaths around multiple axons only in CN
Schwann cell forms one mylein sheath around one section of axon in the peripheral nervous system
What is multiple scelerosis
Degradation of oligodendocytes dying off mylein is degrading different sympotoms
What is guillain-Barre syndrome
Degradation of Schawn cells it is weakness nad paralysis motor problem in younger age
What is gray matter in analogy
It the buildings in a city that process and store information
What is white matter in an analogy
Represents the roads, transit lines and bike lanes that connect the buildings to transmit information
What is the gray matter made up of
Cell bodies cortex and nuclei
Do cell bodies have myelin
No only axons
What is the white made up of
Axons with glial sheath
What do unmyleinated neurons do
Need to depolarize at every point along their axon which leads to a relatively slow signal speed
Where do myelinated neurons
only need to depolarize at the nodes of Ranvier meaning the signal can jump from node to node, drastically increasing the speed
What are the steps of neuronal synapse
- Nerve impulse arrive at axon terminal end bulb of presynaptic neuron
- Impulse cause calcium channels to open and calcium ions rush in
- Neurotransmitter is released and crosses the synaptic cleft to trigger opening of sodium channels on postsynaptic neuron
- Sodium ions flow into dendrite of posysnaptic neuron to initiate new nerve impulse
What is the autonomic nervous system
Autonomic nervous system (ANS)
Peripheral innervation to visceral organs and glands
Peripheral nervous system in charge of invoulntary control
What is the somatic nervous system
Peripheral innervation to all other tissues (muscles, skin etc)
What is the parasympathetic nervous system
feed and breed
rest and digest
What is the sympathetic nervous system
Fight or flight
What is the somatic nervous system
Component of the peripheral nervous system in charge of voulntary and peripheral sensation
What is a dermatome
Skin which is sensory
What is a myotome
Muscle and motor
