M9 MP when stimulated Flashcards
State the 3 main types of gated channels
Chemical gated channel
Voltage gated channel
Mechanical gated channel
State 2 locations where chemical/mechanical gated channels are located
Pacemaker cells
Postsynaptic membrane
Muscle
Nerve endings or receptors
What occurs during input zone?
Production of action potential
What is channel found in trigger zone and where exactly?
Voltage-gated ion channel at axon hillock
In which zone does transmission of information occurs?
Conducting zone
If graded potential is strong enough which ion channel will open and what happens?
Voltage-gated ion channel opens and Na+ influx occurs which result in action potential
What is membrane potential?
The voltage difference between the inside and outside of the cell
Where does graded potential occurs?
Plasma membrane
State 2 characteristics of graded potential
- Amplitude proportional to strength of stimulus
- Can be summed spatially or temporally
Refer to M9 page 31 for better understanding
What is the relationship between AP and GP?
AP is only generated when GP reaches threshold
Is EPSP related to hyperpolarization or depolarization?
Depolarization
What is threshold stimulus?
It is a stimulus that produces a graded potential which is strong enough to stimulate voltage gated channels to open and produce AP
What is sub-threshold stimulus?
it is a graded potential that is not strong enough to stimulate voltage gated channels to open to produce AP
Can hyperpolarization open Voltage gated ion channels?
No
Is the amplitude of AP constant? Give reasons
Yes because the influx of Na determines the depolarizing phase of AP is constant.
