Neurophysiology Part One Flashcards
How do neurons communicate?
Through chemical and electrical signals
What is the difference between a chemical and electrical signal a neuron uses?
A chemical signal is between 2 neurons.
A electrical signal is WITHIN a single neuron
Is a neuronal conduction an electrical or chemical
It is an electrical signal
How is a neuronal conduction made?
Through an action potential
How is a chemical signal made?
through a Synaptic transmission by NTs
What is the specific voltage of a neuron at rest?
-70 mV
Why are Neurons polarized?
There is a charge difference between the inside and the outside of the cell. the inside is more negative than the outside
What are the 5 essential ions associated with a neuron?
- K -Potassium
- Na+ - Sodium
- Cl- chloride
- A- proteins/anions
- Ca+ calcium
Where are each of the 5 ions located at rest?
Na + and Cl- are located outside the cell while K+ and A- are located inside the cell. Ca2+ is also located outside
How do ions move in and out of the cell?
Through Ion channels
What are the 4 ionic forces that help to maintain the resting membrane potential?
- Diffusion
2, Selective Permeability
3.Electrostatic Pressure - Sodium - Potassium Pump
What is diffusion?
Particles are moving down concentration gradient
What is selective permeability?
only certain ions can pass through the membrane easily while others struggle
What is electrostatic pressure?
Similarly charged particles will repel while opposite particles will attract
Of the 4 ionic forces is considered active?
The Sodium-Potassium Pump is active while the other 3 are passive
Outline the Sodium-Potassium Pump:
For every 3 Sodium ions pumped out 2 Potassium ions are returned inside. helps to balance the influx of Na and the efflux of K
What is Neuronal Conduction?
How the neuron functions
Define the term postsynaptic potential:
It is the temporary change in the polarization of a neuron
What are the two possible outcomes of a postsynaptic transmission?
- Depolarization
2. Hyperpolarization
What is meant by depolarization?
What is meant by hyperpolarization?
The resting membrane potential is lowered to - 67
The resting membrane potential is increased to -73
Where does the signal for postsynaptic potential come from?
It comes from the release of the NT from the terminals and in binding to the receptors
What is an excitatory signal?
An EPSP : Excitatory Posynaptic Potential
What do EPSPs do?
Increase the likelihood that the neuron will fire
