Neurophysiology Flashcards
Function of the myelin sheath
1) Covers the axon
2) Insulates the axon
3) Increases speed of nerve impulse
4) Protects the axon
Mitotic activity is lost in most neurons (Amitotic) except:
In the Hippocampus
How many different types of neurotransmitters can a single neuron release?
One
Most abundant neuron in the body
Multipolar neurons
Somatic motor and sensory nerves are __________ received.
Consciously
Visceral sensory and autonomic motor nerves are ___________ received.
Unconsciously
Somatic sensory nerves are found in what 4 locations?
Skin, skeletal muscles, bones, joints
Visceral sensory nerves are found where?
Visceral organs (abdomen) as well as thoracic and abdominal cavities
Somatic motor nerves control what?
Skeletal muscles
Autonomic motor nerves unconsciously control what 3 things?
Glands, cardiac muscle, smooth muscle (blood vessels and GI)
What division of autonomic motor nerves arouse the body to action?
Sympathetic
What division of the autonomic motor nerves have a calming effect?
Parasympathetic
What are the 2 types of nervous tissue?
Neurons and glial cells
Excitable nervous tissue cells are called?
Neurons
Name the 5 characteristics of Neurons
Excitable Conductivity Secretion of neurotransmitters (excitatory or inhibitory) Extreme longevity Amitotic (don’t divide)
A neuron cell body is called the _____ while the long arm that can be covered in myelin or not is called the _______ .
Soma, axon
What part of the neuron summates local potentials that, if added up to -55mV, stimulates an AP?
Axon Hillock
What is the outside and inside of a neuron called?
Axolemma and axoplasma respectively
Each neuron has one axon, but it can be divided into many branches, and each branch is called a _______ or __________ ____________.
Telodendrion or axon terminal
Each telodendrion or axon terminal ends at a __________ ____________, which forms a synapse with another neuron or cell of the target organ.
Synaptic knob
What are the 4 things myelin does for the axon?
Covers
Protects
Insulates
Increases speed of impulse
What structural classification of neuron has many processes that extend from the soma, one being an axon, the others being dendrites. Also the most abundant neuron in the body.
Multipolar
Inter neurons and motor neurons are examples of what structural classification of neuron?
Multipolar
What structural classification of neuron has two processes that extend from the soma, and where are they found in the body?
Bipolar
Eyes, ears, nose (special senses)
What structural classification of neuron is described as having a single, short neuron process that extends directly from the soma like an “on/off” ramp, with a peripheral process that brings information to the soma, and a central process that brings information to the spine (CNS)?
Unipolar neuron
Bonus: they are sensory and the ganglia are located in the ganglia!
All a. motor or b. sensory neuron cell bodies (somas) are in the ______ root ganglion?
Sensory
Dorsal
Unipolar sensory neurons with somas in the dorsal root ganglion synapse with what type of multipolar neuron inside the spine?
Inter neurons
Where is the body (soma) of a motor neuron located?
Within the spine
A cable-like bundle of parallel axons is called a _______ .
Nerve
A thick layer of dense irregular connective tissue that encloses the entire nerve, providing support and protection, is called the ____________.
Epineurium
The layer of dense irregular connective tissue that wraps bundles of axons and supports blood vessels by holding them to fascicles is known as the __________ .
Perineurium
A delicate layer of areolar connective tissue that separates and electrically insulates each axon and has capillaries that supply the axon is called the ________ .
Endoneurium
Cranial nerves extend from the ______ while spinal nerves extend from the ____ _____.
Brain
Spinal cord
Oligodendrocytes, astrocytes, ependymal cells, Schwann cells, satellite cells, and microglia are all ______ cells.
Glial
These glial cells are connected to the axons (CNS), providing support and insulation.
Oligodendrocytes
These glial cells are by far the fewest and seek out pathogens, acting as phagocytes that engulf/destroy microorganisms and cell debris.
Microglia
These glial cells are the most abundant glial cells that have processes which touch capillary walls, helping to form the blood-brain barrier that regulates the passage of substances into the brain. They also for the structural network and occupy the space of dying neurons.
Astrocytes
These glial cells line the ventricles of the brain and central canal of the spinal cord producing CSF
ependymal cells