Ch. 2 Flashcards
where the action potential of the cell is created
axon hillock
short projections from the cell body that serve as the main input site for the cell
dendrite
output unit of the cell, specialized to send information (electrical message) to other neurons, muscles cells, or glands. The nerve transmitter
axon
How do neurons communicate within themselves
electrically
How do neurons communicate with each other
chemically
What are the functions of a neuron
receive (chemical messages from other neurons), integrate (1 neuron can get many messages and condense them into 1), transmit (electrical signals down axon), transfers (chemically between neurons)
moves neurotransmitters and other substances from the soma down the axon toward the presynaptic terminal
anterograde transport
moves substances from the synapse back to the soma
retrograde transport
classification of neurons that have 2 primary processes that extend form the cell body: dendritic root and axon.
bipolar
what type of neuron is the cell of peripheral somatosensation
pseudounipolar
part of a pseudounipolar neuron that functions like a dendrite, so it receives the message that the cell then transmits
peripheral axon
part of a pseudo unipolar neuron that bypasses the cell body and goes into spinal cord where it carries the message to the brain
central axon
classification of neuron that have multiple dendrites arising from many regions of the cell body and a single axon
multipolar
cell of the brain and peripheral motor function
multipolar
small neuron that gets stuck between two others and it’s job is to adjust the messaging
interneuron
what are the 4 types of channels in our membranes
leak, modality-gated, ligand-gated, and voltage-gated
allow diffusion of a small number of ions through the membrane at a slow continuous rate. Must have a driving force and must fit for ions to pass through.
Leak channel
specific to sensory neurons. Open in response to mechanical forces (stretch, touch, and pressure, temperature changes, or chemicals
modality-gated channel
open in response to a neurotransmitter binding to the surface of a channel receptor on a postsynaptic cell membrane. Found on cell bodies and dendrites where they get chemicals from other neurons
ligand-gated channel
open in response to changes in electrical potential across the cell membrane. Channel that conducts an action potential
voltage-gated channel
channels that start the process of changing ions
modality and ligand
the value of the electrical potential across the membrane when a neuron is not transmitting information. The difference in charge from outside to inside a cell
resting potential
which part of the cell has more negative charge
inside
changing what type of of electrical allows our nerves to send signals
resting potential
the driving factor for setting up the difference of charge. Makes the inside of the cell more negative
Na+/K+ ATP pump
Na+/K+ ATP pump transports how many Na+ ions out of cell for every 2 K+ ions it brings in
3
“excitatory”
depolarization
“inhibitory”
hyperpolarization
to create less separation or less difference. Makes the inside less negative relative to the outside of the cell. The way that we create action potentials
depolarization
to create more separation or difference. Makes the inside even more negative than it typically is at rest. Makes it less likely that an action potential will be created
hyperpolarization
what 2 places do local potentials happen
receptors of sensory neurons and at the neurotransmitter or ligand-gated channels on a dendrite
small flows of ions or changes in polarity that take place either at the end of a sensory neuron or at a synapse. Can be “graded.” Passively propagate.
local potential
a change of potential caused by the modality opening gates
receptor potential
a change of potential, either depolarizing or hyperpolarizing , that is caused by neurotransmitters opening ligand-gated channels
synaptic potential
what is the purpose of a local change of potential
to help create action potentials
many repetitive signals arriving at one spot over time.
temporal summation
one signal arriving at many different places
spatial summation
long distance message of the nervous system. Created when voltage-gated channels open and allow enough depolarization to occur
action potential
what 2 places does an action potential start
trigger zone or axon hillock
piece of sensory neuron just proximal to sensor. Has voltage-gated channels in it. If they open, AP is created.
trigger zone
how do action potentials travel
active and passive propagation
period of time where no new action potentials can be created at that spot
absolute
period of time where a new action potential can be created at that spot but only if there is a large stimulus
relative
a period of time where no new action potential can be created at that spot. Ensures the one-way travel of signals.
refractory period
auto-immune attack on Schwann cells (PNS cell myelinators). Can affect sensory, motor, and autonomic peripheral neurons.
Guillain-Barre
auto-immune attack on oligodendrocytes (CNS cell myelinators). Can affect sensory, motor, and autonomic neurons. Typically lose function, neuroinflammation goes away and they can function again. Relapse/remit pattern.
Multiple Sclerosis
type of glia found in the CNS. Have a phagocytic function in injury, destruction of aging neurons, may have started as immune system cells during development, and abnormal activation may contribute to brain disease
microglia
most common type of brain tumor. Tumor creates ischemia. Most common location is in the frontal lobe.
astrocytoma
macroglia cell that provides myelin insulation in the PNS. Has phagocytic function in injury
Schwann cell
macroglia cell that provides myelin insulation in CNS. One to many insulation.
Oligodendrocyte
macroglia cell that is in charge of cell signaling, scavenger function, connecting neurons and capillaries, and provide the pathway for migrating neurons in development
Astrocyte
pathology associated with synaptic transmission of acetylcholine
myasthenia gravis
pathology associated with synaptic transmission of serotonin
depression
end of the axon before the synapse
presynaptic terminal
ligand released from terminal
neurotransmitter
type of channel on the post-synaptic membrane
ligand-gated
space between axon and dendrite (presynaptic and postsynaptic)
synaptic cleft
the very last voltage-gated channels let what ion in during synaptic signaling
calcium
what does calcium do during synaptic signaling
moves ligand to the end of the axon
function of glia
provide structure for neural cells
may assist with transmission of information
May assist with regulation of extracellular fluid
possible role in pathogenesis
when one axon splits into many branches and sends messages to many different target neurons
divergence
when there are many inputs coming to one neuron
convergence
how do you typically name pathways
origin + termination
how does your brain know strength
number of action potentials
