Nervous System - Part 2 Flashcards
What type of input does each neuron usually receive from many neurons?
Synaptic input
What is the name of the terminal membrane facing a dendrite or the soma of the target neuron?
Presynaptic terminal
What is the name of a space that separates the presynaptic terminal from the target cell?
Synaptic cleft
What is the name of the target cell membrane?
Postsynaptic membrane
What is the magnitude or intensity that must be exceeded for a response to occur?
Threshold
What is a propagating change of the resting membrane potential?
Action potential
What is the result of the differential separation of charged ions across the membrane?
Resting membrane potential
Where do positive charges tend to accumulate?
Immediately outside the cell membrane
Where do excess negative charges tend to accumulate?
Immediately inside the cell membrane
Does the inside of the cell become more positive or negative with respect to the exterior?
More negative
What are the 2 types of postsynaptic potentials?
Excitatory and inhibitory
What can change the resting membrane potential of neurons and muscle cells?
The result of synaptic signaling from other cells
What does the synaptic signaling from other cells lead to the formation of?
Postsynaptic potentials
What type of polarization occurs during excitatory postsynaptic potential?
Depolarization
Does the membrane potential during excitatory postsynaptic potential become more negative or positive?
Positive
Does the membrane potential during inhibitory postsynaptic potential become more negative or positive?
Negative
What type of polarization occurs during inhibitory postsynaptic potential?
Hyperpolarization
Where are EPSPs and IPSPs summated at?
The axon hillock
What are the 2 summations?
Spatial and temporal
What is generated if the graded potential exceeds the threshold?
An action potential
What occurs at the initial axon segment?
The action potential
Glycine binds to iontropic receptors for chlorine molecules, which are negative, creating a negative influx into the cell, which one of the postsynaptic potentials is this describing?
Inhibitory postsynaptic potential
Acetylcholine binds to iontropic receptors for sodium molecules, which are positive, creating a positive influx into the cell, which one of the postsynaptic potentials is this describing?
Excitatory postsynaptic potential
What happens when a excitatory neuron fires 2 signals in a row?
Membrane becomes less negative, but not as high as the threshold
What happens when 2 neurons each fire a signal at the same time?
Spatial summation occurs- meaning they produce a membrane potential together that is higher than only one, from different areas of the neuron
What happens when 2 neurons each fire 2 excitatory signals at the same time?
Temporal and spatial summation occur- the produced wave surpasses the threshold potential
What type of channels are at the end of the presynaptic terminal?
Calcium
What is it called when the membrane potential declines after it has reached the climax, but hasn’t come back down to the threshold yet?
Repolarization
