Pre-Lab
An action potential requires _______.
An action potential requires _______.
sodium to flow with its electrochemical gradient
voltage-gated sodium channels to open
voltage-gated sodium channels to open and sodium to flow with its electrochemical gradient
chemically gated sodium channels to open
To reach threshold, the amount of sodium _______.
To reach threshold, the amount of sodium _______.
entering the cell must overcome the potassium exiting
exiting the cell must overcome the potassium entering
entering the cell must overcome the potassium entering
exiting the cell must overcome the potassium exiting
Which of the following blocks voltage-gated sodium channels?
Which of the following blocks voltage-gated sodium channels?
potassium
tetrodotoxin and lidocaine
tetrodotoxin
lidocaine
Which of the following is used to block pain?
Which of the following is used to block pain?
potassium
tetrodotoxin and lidocaine
tetrodotoxin
lidocaine
Post-Lab
Which of the following occurred in the presence of tetrodotoxin?
Which of the following occurred in the presence of tetrodotoxin?
The size of the action potential increased.
The size of the action potential decreased.
The number of action potentials decreased.
The number of action potentials increased.
Which of the following occurred in the presence of tetrodotoxin?
Which of the following occurred in the presence of tetrodotoxin?
An action potential was always seen at R1.
An action potential was always seen at R2.
An action potential was always seen at R1 and R2.
All action potentials were missing.
In the presence of lidocaine, the action potential was NOT affected at R1 because _______.
In the presence of lidocaine, the action potential was NOT affected at R1 because _______.
lidocaine was applied downstream of R1
lidocaine doesn't have an effect on the generation of action potentials
lidocaine was applied upstream of R1
there are no voltage-gated sodium channels to be affected
The effects of lidocaine and tetrodotoxin were _______.
The effects of lidocaine and tetrodotoxin were _______.
identical
similar, but lidocaine had a greater effect
very different, because lidocaine had no effect
similar, but tetrodotoxin had a greater effect