UCI Bio Sci E109 Module 1 &2 Questions With Complete
Solutions
[ Select ] ["Voltage-gated", "Ligand-gated", "Optically-gated",
"Mechanically-gated"] channels are critical for human hearing,
whereas [ Select ] ["Mechanically-gated", "Voltage-gated",
"Optically-gated", "Ligand-gated"] channels respond to
neurotransmitters, and [ Select ] ["Optically-gated", "Voltage-
gated", "Mechanically-gated", "Ligand-gated"] channels are
sensitive to changes in electrical activity across a membrane.
Correct Answers 1. [Mechanically-gated]
2. [Ligand-gated]
3. [Voltage-gated]
At time i, what is the most likely state of a Na+ channel?
The activation gate is open and the inactivation gate is closed
Both gates are closed
Both gates are open
The activation gate is closed and the inactivation gate is open
Correct Answers The activation gate is open and the
inactivation gate is closed
By what factor would the rate of diffusion change if membrane
thickness increased by a factor of 5? Correct Answers 0.200
Can another action potential be triggered at time vi?
Yes, but the threshold is greater than -55 mV.
No, it is not possible to trigger an AP at that time.
, Yes, but the peak Vm will be lower than at time iii Correct
Answers Yes, but the threshold is greater than -55 mV.
Channel proteins are capable of active transport.
True
False Correct Answers False
Choose the level(s) of biological organization that pertain to
physiology, in this course:
populations
ecological systems
tissues
molecules Correct Answers tissues
molecules
How would the equilibrium potential for potassium (EK+)
change if the concentration of that ion increased outside of a
cell? Correct Answers It would increase
Imagine an exercising muscle cell that requires a constant
supply of oxygen to avoid fatigue. At which of the following
distances from a capillary would you predict these muscle cells
to have sufficient oxygen delivery?
0.5 m
2 nm
2 mm
20 nm Correct Answers We know from the lecture material
that a diffusion can transport in 1 ms over a distance of 20 nm,
so it should be even faster at shorter distances.
Solutions
[ Select ] ["Voltage-gated", "Ligand-gated", "Optically-gated",
"Mechanically-gated"] channels are critical for human hearing,
whereas [ Select ] ["Mechanically-gated", "Voltage-gated",
"Optically-gated", "Ligand-gated"] channels respond to
neurotransmitters, and [ Select ] ["Optically-gated", "Voltage-
gated", "Mechanically-gated", "Ligand-gated"] channels are
sensitive to changes in electrical activity across a membrane.
Correct Answers 1. [Mechanically-gated]
2. [Ligand-gated]
3. [Voltage-gated]
At time i, what is the most likely state of a Na+ channel?
The activation gate is open and the inactivation gate is closed
Both gates are closed
Both gates are open
The activation gate is closed and the inactivation gate is open
Correct Answers The activation gate is open and the
inactivation gate is closed
By what factor would the rate of diffusion change if membrane
thickness increased by a factor of 5? Correct Answers 0.200
Can another action potential be triggered at time vi?
Yes, but the threshold is greater than -55 mV.
No, it is not possible to trigger an AP at that time.
, Yes, but the peak Vm will be lower than at time iii Correct
Answers Yes, but the threshold is greater than -55 mV.
Channel proteins are capable of active transport.
True
False Correct Answers False
Choose the level(s) of biological organization that pertain to
physiology, in this course:
populations
ecological systems
tissues
molecules Correct Answers tissues
molecules
How would the equilibrium potential for potassium (EK+)
change if the concentration of that ion increased outside of a
cell? Correct Answers It would increase
Imagine an exercising muscle cell that requires a constant
supply of oxygen to avoid fatigue. At which of the following
distances from a capillary would you predict these muscle cells
to have sufficient oxygen delivery?
0.5 m
2 nm
2 mm
20 nm Correct Answers We know from the lecture material
that a diffusion can transport in 1 ms over a distance of 20 nm,
so it should be even faster at shorter distances.
