PNB 2274 UConn Exam 2 Tanner
Complete set with Questions and correct
Answers
Principles Electrostatic Attraction - correct answer- ✅- charge attraction
- positively charged ions will be attracted to negatively charged ions
Principles Chemical (diffusional) Gradients - correct answer- ✅- when a membrane is
selectively permeable positively charged ions will flow to the one side making the other side
negative due to leak channels.
- making one side harder to diffuse with the outside of the cell because it is attracted to the more
charged side.
Relate diffusional and electrical gradients to behavior of ions - correct answer- ✅- individually
ions will be attracted to one another if opposite charges
- A Nernst equilibrium forms when there is a balance of ions between the electrostatic attraction
and diffusional gradient of the ions
- no ion wants to flow either in or out of the cell.
Principles of Equilibrium - correct answer- ✅membrane potential at which an ion's net flux is 0
Nernst Equation - correct answer- ✅-used for only one ion at a time
-Ex = equilibrium potential
-determines the electrical potential (voltage) at which diffusion flow of an ion one way is
balanced by electrostatic attraction in the other
What effect Equilibrium Potential ( Ex) ? - correct answer- ✅- temperature
- Concentration of ion
Mammalian ion concentrations and Nernst Potentials - correct answer- ✅Ek = -90, ECl = -70,
ENa = +60, ECa = +130
- these values can change based on condition
Goldman- Hodgkin- Katz Equation - correct answer- ✅-the membrane is permeable to more
than 1 ion at rest
-Vm = membrane potential when net flux of all other ions together is 0
-membrane have one Vm value; it is the average Ex values for each ion
- ** permeability matters
Goldman Equation: Multiple ion Case - correct answer- ✅Vm is somewhere between the
largest Ex and smallest Ex.
, Goldman Equation: One ion Case - correct answer- ✅- GHK reduces to Nernst
- Vm approximates Ex of the most permeant ion
Depolarization - correct answer- ✅- Changing membrane potential to be more positive (MORE
+)
Hyperpolarization - correct answer- ✅- Changing membrane potential to be more negative
(MORE -)
Repolarization - correct answer- ✅Returning membrane potential
towards rest potential
Dendrite - correct answer- ✅- input signal
-receive incoming signals
-passive, graded synaptic potentials
Axon - correct answer- ✅-output signal
-an all-or-nothing action potential
Action Potentials - correct answer- ✅- Active
- no decrement with distance or time
- "All or none"
- SUPRA- threshold
- are key in axons and muscle cells.
Graded Potentials - correct answer- ✅- Passive or "electronic"
- degrade with distance and time
- variable amplitude
- SUB-threshold : no A.P.
- are most relevant to dendrites and the motor endplate
What happens when the action potential is fired? - correct answer- ✅-a wave of elevated
potential, results in vesicle release, muscle contraction, signal propagation.
-also called "spikes"
-cyclic process of channel opening and closing
When a "triggerzone" for action potential is initiated... - correct answer- ✅-high density of
voltage-gated sodium channels that trigger action potentials open
-ultimate "output" of dendritic integration
Steps of action potential firing - correct answer- ✅1. cell starts at resting membrane potential
(polarized) until there is a depolarization stimulus.
Complete set with Questions and correct
Answers
Principles Electrostatic Attraction - correct answer- ✅- charge attraction
- positively charged ions will be attracted to negatively charged ions
Principles Chemical (diffusional) Gradients - correct answer- ✅- when a membrane is
selectively permeable positively charged ions will flow to the one side making the other side
negative due to leak channels.
- making one side harder to diffuse with the outside of the cell because it is attracted to the more
charged side.
Relate diffusional and electrical gradients to behavior of ions - correct answer- ✅- individually
ions will be attracted to one another if opposite charges
- A Nernst equilibrium forms when there is a balance of ions between the electrostatic attraction
and diffusional gradient of the ions
- no ion wants to flow either in or out of the cell.
Principles of Equilibrium - correct answer- ✅membrane potential at which an ion's net flux is 0
Nernst Equation - correct answer- ✅-used for only one ion at a time
-Ex = equilibrium potential
-determines the electrical potential (voltage) at which diffusion flow of an ion one way is
balanced by electrostatic attraction in the other
What effect Equilibrium Potential ( Ex) ? - correct answer- ✅- temperature
- Concentration of ion
Mammalian ion concentrations and Nernst Potentials - correct answer- ✅Ek = -90, ECl = -70,
ENa = +60, ECa = +130
- these values can change based on condition
Goldman- Hodgkin- Katz Equation - correct answer- ✅-the membrane is permeable to more
than 1 ion at rest
-Vm = membrane potential when net flux of all other ions together is 0
-membrane have one Vm value; it is the average Ex values for each ion
- ** permeability matters
Goldman Equation: Multiple ion Case - correct answer- ✅Vm is somewhere between the
largest Ex and smallest Ex.
, Goldman Equation: One ion Case - correct answer- ✅- GHK reduces to Nernst
- Vm approximates Ex of the most permeant ion
Depolarization - correct answer- ✅- Changing membrane potential to be more positive (MORE
+)
Hyperpolarization - correct answer- ✅- Changing membrane potential to be more negative
(MORE -)
Repolarization - correct answer- ✅Returning membrane potential
towards rest potential
Dendrite - correct answer- ✅- input signal
-receive incoming signals
-passive, graded synaptic potentials
Axon - correct answer- ✅-output signal
-an all-or-nothing action potential
Action Potentials - correct answer- ✅- Active
- no decrement with distance or time
- "All or none"
- SUPRA- threshold
- are key in axons and muscle cells.
Graded Potentials - correct answer- ✅- Passive or "electronic"
- degrade with distance and time
- variable amplitude
- SUB-threshold : no A.P.
- are most relevant to dendrites and the motor endplate
What happens when the action potential is fired? - correct answer- ✅-a wave of elevated
potential, results in vesicle release, muscle contraction, signal propagation.
-also called "spikes"
-cyclic process of channel opening and closing
When a "triggerzone" for action potential is initiated... - correct answer- ✅-high density of
voltage-gated sodium channels that trigger action potentials open
-ultimate "output" of dendritic integration
Steps of action potential firing - correct answer- ✅1. cell starts at resting membrane potential
(polarized) until there is a depolarization stimulus.
