2. Electrophysiological Principles Flashcards
information transfer along neurons occurs via the movement of:
ions
neurons can produce a change in membrane potential known as the:
action potential
stimulus intensity can be encoded by the _____ of action potentials a neuron produces
frequency
information is passed from neuron to neuron at the:
synapse
the plasma membrane is a _____ that has many types of proteins associated with it
lipid bilayer
water and ions move into and out of the cell through:
ion channels and pores in the membrane
the two main types of lipids found in nerve cell membranes are:
glycerophospholipids and sphingolipids
what types of cells have a membrane potential?
all cells (including plants and single celled organisms)
excess ions collect along a thin shell on the inner and outer surfaces of the:
plasma membrane
true or false: the bulk of the intracellular and extracellular fluid is electrically neutral
true
what is the resting membrane potential?
-60mV
why is the resting membrane potential negative?
the inside of the cell is approximately 60mV negative with respect to the outside
tells you about the relationship between current, resistance, and potential
Ohm’s law
what is the formula for Ohm’s law?
V = IR
what is voltage according to Ohm’s law?
the voltage between two points is the cost in energy (work done) required to move a unit of charge from the more negative point (lower potential) to the more positive point (higher potential)
voltage is also called the:
potential difference
a Joule of work (J) is needed to move a Coulomb of charge (C) through a potential difference of:
one Volt (V)
what is current (I)?
the rate of flow of electric charge past a point
by convention, current in a circuit always flows from a more _____ point ot a more _____ point even though the actual electron flow is _____
positive, negative, in the opposite direction
a current of one ampere (A) equals a flow of:
one coulomb of charge per second (C/s)
what is the formula for current?
I = Q/t
Q = charge
t = time
the current through a conductor is proportional to the voltage across it. this constant of proportionality is known as:
conductance (g)
what is the formula for conductance?
g = I/V or g = 1/R
what is a capacitor?
something that stores charge. it is an insulator that separates two conductors