Neurophysiology of Nerve Impulses Equipment used:
a) Activity 1: The Resting Membrane Potential
b) Activity 2: Receptor Potential
c) Activity 3: The Action Potential: Threshold
d) Activity 4: The Action Potential Importance of Voltage - Gated Na+ channels
e) Activity 5: The Action Potential: Measuring Its Absolute and Relative Refractory
Periods
f) Activity 6: The Action Potential: Coding for Stimulus Intensity
g) Activity 7: The Action Potential: Conduction Velocity
h) Activity 8: Chemical Synaptic Transmission and Neurotransmitter Release
I) Activity 9: The Action Potential: Putting It All Together
,Give this one a try later!
a) & b) Neuron(in vitro) - a large, dissociated(or cultured) neuron.
3 extracellular solutions - control, high potassium, and low sodium.
Microelectrode - a probe w/ a very small tip that can impale a single
neuron(in an actual wet lab, a microelectrode manipulator is used to
position the microelectrode. For simplicity, the microelectrode manipulator
will not be depicted in this activity.)
Microelectrode Manipulator Controller - controls movement of the
manipulator.
Microelectrode Amplifier - used to measure the voltage between the
microelectrode and a reference.
Oscilloscope - used to observe voltage changes.
c) Nerve Chamber
-Axon
-Oscilloscope - used to observe timing of stimuli and voltage changes in
the axon.
-Stimulator - used to set the stimulus voltage and deliver pulses that
depolarize the axon.
-Stimulating Wires (S)
-Recording electrodes (wires R1 and R2) - used to record voltage changes
in the axon (The first set of recording electrodes, R1, is 2 cm from the
stimulation wires, and the second set of recording electrodes, R2, is 2 cm
from R1).
d) same as c) and: -Tetrodotoxin (TTX) and Lidocaine
e) and f) are same as c) except only has Recording electrode R1 - used to
record voltage changes in the axon. (2cm from stimulation wires).
g) Nerve Chamber
- 3 axons, Fibers A, B and C
-Oscilloscope - used to observe timing of stimuli and voltage changes in
the axon.
-Stimulator - used to set the stimulus voltage and deliver pulses that
depolarize the axon.
-Stimulating Wires (S)
-Recording electrodes (wires R1 and R2) - used to record voltage changes
in the axon (The first set of recording electrodes, R1, is 2 cm from the
stimulation wires, and the second set of recording electrodes, R2, is 2 cm
from R1).
, h) Neuron(in Vitro) - a large, dissociated (or cultured) neuron with
magnified axon terminal
-4 extracellular solutions - control Ca2+, no Ca2+, low Ca2+, and Mg2+
I) Sensory neuron(in Vitro) - a large, dissociated(or cultured) neuron
-Interneuron(in Vitro) - a large, dissociated(or cultured) interneuron
-Microelectrodes - small probes w/ very small tips that can impale a single
neuron (In an actual wet lab, a microelectrode manipulator will not be
depicted in this activity.)
-Hook electrodes - used to record extracellular voltage changes in the
axon.
-Oscilloscope - used to observe the changes in voltage across the
membrane of the neuron and interneuron.
-Stimulator - used to set the stimulus intensity(low to high) and to deliver
pulses to the neuron.
b) Barany Test
Give this one a try later!
experiment:
- have subject sit in rotating chair
- subject Must keep eyes OPEN
- head tilted forward 30 degrees (to stimulate semi-circular canals)
- spin chair 10 revolutions in 10 seconds then STOP chair
response:
- eyes moved left to right, body trembling, increased heart rate, dizziness
normal response: subject will feel like chair is still rotating even after it's
stopped and WILL demonstrate nystagmus
g) Photopupillary Reflex
(done already in reflex lab)
Give this one a try later!
, experiment:
- shine light into eye
response:
- eye will constrict
Egg Questions:
a) what egg 1 in distilled water represent?
b) what egg 2 in sucrose represent?
c) what is a hypotonic solution?
d) what is a hypertonic solution?
Give this one a try later!
a) Hypotonic Solution
b) Hypertonic Solution
c) Cell takes in water. Contains lower concentration of solutes surrounding
the cell than are present inside the cell. (cell will have a swollen shape)
d) Cell loses water. Contains a higher concentration of solutes than are
present inside the cells. (cell will shrink in shape)
dialysis questions:
a) What is the Benedict's test? And how do you know if the test is positive?
b) Why did H20 enter sac 1, sac 3 and sac 4?
a) Activity 1: The Resting Membrane Potential
b) Activity 2: Receptor Potential
c) Activity 3: The Action Potential: Threshold
d) Activity 4: The Action Potential Importance of Voltage - Gated Na+ channels
e) Activity 5: The Action Potential: Measuring Its Absolute and Relative Refractory
Periods
f) Activity 6: The Action Potential: Coding for Stimulus Intensity
g) Activity 7: The Action Potential: Conduction Velocity
h) Activity 8: Chemical Synaptic Transmission and Neurotransmitter Release
I) Activity 9: The Action Potential: Putting It All Together
,Give this one a try later!
a) & b) Neuron(in vitro) - a large, dissociated(or cultured) neuron.
3 extracellular solutions - control, high potassium, and low sodium.
Microelectrode - a probe w/ a very small tip that can impale a single
neuron(in an actual wet lab, a microelectrode manipulator is used to
position the microelectrode. For simplicity, the microelectrode manipulator
will not be depicted in this activity.)
Microelectrode Manipulator Controller - controls movement of the
manipulator.
Microelectrode Amplifier - used to measure the voltage between the
microelectrode and a reference.
Oscilloscope - used to observe voltage changes.
c) Nerve Chamber
-Axon
-Oscilloscope - used to observe timing of stimuli and voltage changes in
the axon.
-Stimulator - used to set the stimulus voltage and deliver pulses that
depolarize the axon.
-Stimulating Wires (S)
-Recording electrodes (wires R1 and R2) - used to record voltage changes
in the axon (The first set of recording electrodes, R1, is 2 cm from the
stimulation wires, and the second set of recording electrodes, R2, is 2 cm
from R1).
d) same as c) and: -Tetrodotoxin (TTX) and Lidocaine
e) and f) are same as c) except only has Recording electrode R1 - used to
record voltage changes in the axon. (2cm from stimulation wires).
g) Nerve Chamber
- 3 axons, Fibers A, B and C
-Oscilloscope - used to observe timing of stimuli and voltage changes in
the axon.
-Stimulator - used to set the stimulus voltage and deliver pulses that
depolarize the axon.
-Stimulating Wires (S)
-Recording electrodes (wires R1 and R2) - used to record voltage changes
in the axon (The first set of recording electrodes, R1, is 2 cm from the
stimulation wires, and the second set of recording electrodes, R2, is 2 cm
from R1).
, h) Neuron(in Vitro) - a large, dissociated (or cultured) neuron with
magnified axon terminal
-4 extracellular solutions - control Ca2+, no Ca2+, low Ca2+, and Mg2+
I) Sensory neuron(in Vitro) - a large, dissociated(or cultured) neuron
-Interneuron(in Vitro) - a large, dissociated(or cultured) interneuron
-Microelectrodes - small probes w/ very small tips that can impale a single
neuron (In an actual wet lab, a microelectrode manipulator will not be
depicted in this activity.)
-Hook electrodes - used to record extracellular voltage changes in the
axon.
-Oscilloscope - used to observe the changes in voltage across the
membrane of the neuron and interneuron.
-Stimulator - used to set the stimulus intensity(low to high) and to deliver
pulses to the neuron.
b) Barany Test
Give this one a try later!
experiment:
- have subject sit in rotating chair
- subject Must keep eyes OPEN
- head tilted forward 30 degrees (to stimulate semi-circular canals)
- spin chair 10 revolutions in 10 seconds then STOP chair
response:
- eyes moved left to right, body trembling, increased heart rate, dizziness
normal response: subject will feel like chair is still rotating even after it's
stopped and WILL demonstrate nystagmus
g) Photopupillary Reflex
(done already in reflex lab)
Give this one a try later!
, experiment:
- shine light into eye
response:
- eye will constrict
Egg Questions:
a) what egg 1 in distilled water represent?
b) what egg 2 in sucrose represent?
c) what is a hypotonic solution?
d) what is a hypertonic solution?
Give this one a try later!
a) Hypotonic Solution
b) Hypertonic Solution
c) Cell takes in water. Contains lower concentration of solutes surrounding
the cell than are present inside the cell. (cell will have a swollen shape)
d) Cell loses water. Contains a higher concentration of solutes than are
present inside the cells. (cell will shrink in shape)
dialysis questions:
a) What is the Benedict's test? And how do you know if the test is positive?
b) Why did H20 enter sac 1, sac 3 and sac 4?
