Nervous System Part 1 Flashcards
Peripheral nervous system (PNS)
Nurse extend to outline or peripheral parts of the body
Autonomic nervous system
Consists of structures that regulate the bodies automatic or involuntary functions. A subdivision of the peripheral nervous system
What do neurons do
Conduct impulses
What do glia do
Support neurons
Three main parts of a neuron
The cell body, dendrites, and axon
Three types of neurons
Sensory neuron’s, motor neurons, interneurons
Sensory neuron’s are also called what
Afferent neurons
Motor neuron’s are also called what
Efferent neurons
What is an efferent neuron?
They transmit impulses in the opposite direction, away from the brain and spinal cord
What is a motor neuron
They transmit impulses in the opposite direction, away from the brain and spinal cord
What is a sensory neuron
They transmit impulses to the spinal cord and brain from all parts of the body body
What is an afferent neuron
Transmit impulses to the spinal cord and brain from all parts of the body
What is an interneuron
Conduct impulses from sensory neuron’s to motor neuron’s
Myelin
A white, fatty substance formed by Schwann cells the wraparound some axons outside the central nervous system
What is the axon surrounded by
Myelin
Myelinated fibers
Wraparound some axons outside the central nervous system
Nodes of Ranvier
Our intentions between adjacent Schwan cells.
Neurilemma
The outer cell membrane of a Schwann cell
Function of Glia cells
To hold the functioning neurons together and protect them
Glioma
One of the most common types of brain tumors that develop from Glia
Astrocytes
Glia cells with thread like branches that attach to neuron’s into small blood vessel’s and hold the structures close to each other
Blood brain barrier (BBB)
A two layer structure formed by astrocyte branches. It separates the blood tissue and nervous tissue to protect vital brain tissue from harmful chemicals that might be in the blood
Microglia
Glia cells that are smaller than astrocytes. They usually remain stationary, but inflamed or degenerating brain tissue, they and large, move about, and act as microbe eating scavengers.
Oligodendrocytes
Help to hold nerve fibers together and also serve another and probably more important function; they produce the fatty myelin sheath that enevelips nerve fibers located in the brain and spinal cord. (Gli cell)
Schwan cells
Are glial cells that also for myelin sheaths but do so only in the peripheral nervous system
Nerve
A group of peripheral nerve fibers bundle together like the strands of a cable
Tracts
Made up of bundles of axons in the CNS
White matter
Bundles of axons in the CNS, tracts, are myelinated in this form white matter
Gray matter
Brain and cord tissue composed of cell bodies and unmyelinated axons and dendrites
Endoneurium
A thin wrapping of fibrous connective tissue you that surrounds each Exxon in a nerve
Groups of Endoneurium wrapped axons
Fascicles
Perineurium
A thin fibrous tissue surrounding each fascicle
Epineurium
A tough fibrous sheet that covers the whole nerve
Action potential
Nerve impulse
Reflex arc
A basic type of neuron pathway
Receptors
Are at the beginnings of dendrites of sensory neuron’s
Ganglion
A group of nerve cell bodies located in the peripheral nervous system
Synapse
A microscopic space that separates the axon endings of one year on from the dendrites of another
Effector
And organ that puts nerve signals into effect
Reflex
The response to impulse conduction over a reflex arc
With drawl will reflex
A three neuron arc
Central Nervous System (CNS)
The brain and spinal cord
