Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
38 Cards in this Set
- Front
- Back
|
What causes the voltage- gated channels to open?
|
A change in membrane potential.
|
|
|
Where are Na/K voltage gated channels found?
|
Axon hillock and axon
|
|
|
Where are ligand-gated ion channels found?
|
Cell body and dendrites
(slide 21) |
|
|
In what position are the activation gate and the inactivation gate in when a voltage-gated Na+ channel is capable of opening?
|
Activation gate: Closed
Inactivation gate: Open |
|
|
Which gate is slow?
|
Inactivation gate
|
|
|
How many gates are in a voltage gated K+ channel? Fast or slow?
|
a.1 gate
b.slow. |
|
|
An action potential includes what three phases?
|
Depolarization, repolarization, and hyperpolarization
|
|
|
The membrane potential becomes more _____ during depolarization and more ______ during hyperpolarization.
|
a. More positive
b. More negative |
|
|
A graded potential occurs when the membrane potential is between what two values?
|
-70mV and -55mV
|
|
|
What are the positions of the voltage gated channels for Na+ and K+ when the cell is at rest?
|
Na+ Act: Closed
Na+ Inact: Open K+: Closed |
|
|
A graded potential is ________ when it is depolarizting.
|
Excitatory
|
|
|
A graded potential is _________ when is it hyperpolarizing.
|
Inhibitory
|
|
|
____________ determine whether or not an action potential will occur.
|
Graded potential
|
|
|
What must a graded potential reach in order for an action potential to take place?
|
Threshold (-55mV)
|
|
|
Graded potentials are spread by what?
|
Electrotonic conduction
|
|
|
Do action potentials get stronger or weaker as they travel?
|
Weaker
|
|
|
The magnitude of the graded potential is directly related to what?
|
The strength of the stimulus
|
|
|
What type of summation results when different stimuli overlap in time?
|
Spatial Summation
|
|
|
What type of summation results when the same stimulus is repeated close together?
|
Temporal summation
|
|
|
When an excitatory graded potential is followed by an inhibitory graded potential of equal magnitude, what type of summation occurs?
|
Cancelling Effects
|
|
|
What are the five types of graded potential?
|
1. Postsynaptic
2. Receptor 3. End-plate 4. Pacemaker 5. Slow Wave (Remember: PREPS) |
|
|
When an action potential takes place, the graded potential spreads from the ____________ to the _____________.
|
a. dendrites/cell body
b. axon hillock |
|
|
In what position are the Na+ and K+ voltage gated ion channels during depolarization?
|
Na+ Act:Open
Na+ Inact: Open K+: Closed |
|
|
In what position are the Na+ and K+ voltage gated ion channels during repolarization?
|
Na+ Act: Open
Na+ Inact: Closed K+: Open |
|
|
In what position are the Na+ and K+ voltage gated ion channels during hyperpolarization?
|
Na+ Act: Closed
Na+ Inact: Closed K+: Open |
|
|
What refractory period is still capable of experiencing an action potential?
|
Relative refractory period
|
|
|
In what position are the Na+ and K+ voltage gated ion channels during a relative refractory period?
|
Na+ Act: Closed
Na+ Inact: Open K+: Closed |
|
|
What refractory period is not capable of experiencing an action potential?
|
Absolute refractory period
|
|
|
In what position are the Na+ and K+ voltage gated ion channels during a absolute refractory period?
|
Na+ Act: Closed
Na+ Inact: Closed K+: Open |
|
|
What two things help return the cell back to rest?
|
Leak and Gated channels
|
|
|
The strength of the stimulus will increase the__________ of the action potential.
|
frequency
|
|
|
In what refractory period can a neuron not be stimulated?
|
Absolute
|
|
|
What are the two types of conduction?
|
Saltatory and electrotonic
|
|
|
How does an action potential travel through an electrotonic conduction?
|
The the cell body
|
|
|
What type of conduction occurs within myelinated axons?
|
Saltatory
|
|
|
During saltatory conduction, action potentials jump from ______ to ______.
|
a. nodes
b. nodes |
|
|
What are gaps in the myelin sheath refered as?
|
Nodes of Ranvier
|
|
|
In myelinated fibers,action potentials are preduced where?
|
Nodes of Ranvier
(Pg. 190) |
