Neurophysiology (scavma) Flashcards
Neurons
Functional units of the nervous system
Primary function of nervous system
To receive information form the environment and act on this information
Signal information pathway through nervous system
Environment- sensory receptor- receptor (generator) potential- CNS- action potentials- output, muscle contraction
CNS signal information
Action potential reaches CNS
then have synaptic transmission, post synaptic potentials, integration and action potentials which then leave
Sensory transduction
Physical or chemical signal from environment is changed to an electrical signal known as receptor potential or generator potential which can lead to a potential
Transient electrical signals
Generator potentials, Postsynaptic potentials also and action potentials
Convey info within and between the cells of the nervous system , all result in brief membrane changes
Membrane potential
Exchange of ions across the membrane is responsible for this potential and bioelectrical activity of the neuron
Extracellular Na and Cl
Higher than intracellular and reverse for K, higher intracellular
Electrical Potential
Difference between intracellular and extracellular fluid compartments
Intracellular is negative vs extracellular= membrane potential
Depolarizing
Towards 0 and extracellular potential
Hyperpolarization
More negative
Resting potential
Resting, steady state
Excess of + along outside of membrane and - along inside
3 influential factors in ion movement
Concentration gradient, voltage gradient, membrane permeability
Voltage gradients
For Na and K are inside because cell is negative
For Cl is outwards because attracted by outside +
Net flux
Movement of ions across a membrane dependent on both the forces or gradients acting on that ion and permeability of the cell membrane to that ion
Flux= Pion x driving force
