L6 Nerve Physiology Flashcards
Neurons ____ and _____ a signal to another location. They have _____, do not _____, have high ____ and require abundant _____ and ______.
receives
transmits
longevity
divide
metabolic rate
oxygen, glucose
Dendrites _____ the signal and carry the ____ conduction towards the _____.
receive
nerve
cell body
Axon Hillock is the area on the ____ where the AP builds up ____ it transmits the signal down the axon.
soma
before
Axoplasmic transport is the movement of ____ and ____ between the _____ and _____.
nutrients
wastes
cell body
axon terminals
What are the classifications of neurons?
Multipolar
-many dendrites & 1 axon
Bipolar
-2 processes extend from opposite sides of soma.
Unipolar
-1 short process emerging from soma, branches into a T.
Sensory neurons transmit impulses towards the _____. They originate in the _____ and terminate in the ____.
CNS
PNS
CNS
Motor neurons transmit impulses from the ___ to_______. They originate in the ____ and terminate in the ____.
CNS
efferent organs
CNS
PNS
Interneurons connect ___ neurons to ____ neurons within the ____ and _____. They originate and terminate in the _____.
sensory
motor
spinal cord
brain
CNS
What are the 5 types of glial cells?
Oligodendrocytes
Astrocytes
Microglia
Schwann cells
Ependymal cells
Oligodendrocytes are ____ and ___ cells. They form ______ in the CNS to speed up the _________. _____ acts as a electrical ____.
large
complex
myelin sheath
nerve conduction
Myelin
insulator
Between the myelin sheaths are the ______ which are the ___ regions of axonal membranes only found in ____ axons.
Nodes of Ranvier
bare
myelinated
Unmyelinated axons have ___ conduction
Myelinated axons have ____ conduction
linear
saltatory
Benefits of saltatory conduction?
-Much faster
-Energy efficient. Na+ K+ pump has to restore ions only at the Node of Ranvier compared to throughout the nerve fibers.
(less ATP used )
_______ is another cell that forms myelin sheath but in the ____. Each cell only forms ____ myelin sheath.
Schwann cells
PNS
one
Astrocytes ____ its arms around capillaries and ____ to physically support them. They transmit _____ from capillaries to neurons. They form ______ to protect then neuron from harmful substances in the blood.
wrap
neurons
materials
blood-brain-barrier ( BBB)
_____ act as macrophages and become actively ____ during injury. They are supporting cells in the ____.
Microglia
phagocytic
CNS
Ependymal cells secrete _____, functions as ____ cells, act as ____ between compartments.
CSF
neural stem
barrier
A synapse is the ____ at which ___ neurons communicate, or a neuron and its target organ.
site
two
The neuron that conducts the signal towards the synapse is called _______. and transmits the signal away is called ______,
presynaptic neuron
postsynaptic neuron
The space between neurons is called ________.
synaptic cleft
The AP travels from the ____ of ____neuron -> ______ -> ___ of ____ neuron
axon, presynaptic
synaptic cleft
dendrite, postsynaptic
What are the 3 types of synapses?
Axosomatic ( axon touches soma )
Axodendritic ( axon touches dendrite )
Axoaxonic ( axon touches axon )
The enlarged knob of the axon is called the ____.
presynaptic terminal
The vesicles of axon terminals contain the neurotransmitter ______.
acetylcholine
