physio exam 3 quizzes

Rapid change in membrane potential conducted along the membrane?

action potential

The average resting membrane potential of an axon is

-70 mV

Ion channels that open in response to depolarization are called

ion gated channels

blocking what channels would prevent neuron depolarization

Na

during an action potential what causes depolarization

Na influx

local anesthetics block conduction of action potentials in sensory neurons

inhibiting the release of acetylcholine

what rule is that an axon will depolarize only if the membrane potential reached between -70 and -55 mV

all or none law

the minimum depolarization needed to open Na gates is called

threshold

the period of time when Na channels are recovering from their inactive state and K channels are still open is the

repolarization and relative refractory period are correct

which ions movements is responsible for repolarization

outward diffusion of K

what process is needed to return a membrane to its resting membrane potential with all ions in the correct locations

Na K pump

As the intensity of a stimulus increase more axons will become activated this is called

recruitment

action potentials would be conducted most rapidly by

a myelinated axon with the largest diameter

conduction of an action potential in a myelinated axon is called

saltatory conduction

in a myelinated axon Na channels are

concentrated at the nodes of Ranvier

chemicals that stimulate action potentials in postsynaptic cells are called

neurotransmitters

neurotransmitter release would be inhibited by

blocking Ca2 influx in the axon terminal

The binding of a neurotransmitter to its receptor protein causes ion channels to open in the post-synaptic membrane. What type of gates are these?

chemically regulated gates and ligand regulated gates

what action produces an IPSP on the postsynaptic membrane

opening of Cl channels into the neuron

acetylcholine can induce hyperpolarization by

binding to muscarinic receptors

at what region of the neuron are action potentials first produced

initial segment of an axon

spatial summation

occurs because of the convergence of many neurons on a single postsynaptic cell

temporal summation

occurs when a single neuron releases neurotransmitters rapidly

when the nerve is stimulated at a voltage of 1 what is the response of the oscilloscope

no response

when a nerve is exposed to sodium chloride, is an action potential generated?

no

how would you describe the trace that is generated when the nerve is exposed to ether

trace is a flat line

what was the effect of curare on the action potential

no effect

what happens when lidocaine is applied to the nerve and the nerve is stimulated at the threshold level

trace is a flat line

interoreceptors are located

in internal visceral organs

cutaneous receptors are in

skin

lamellar corpuscles are a type of

encapsulated nerve ending

This receptor for light touch is made up of a free nerve ending associated with a special epidermal cell.

tactile/mekel disc

what is the most numerous cutaneous receptor type

receptors for pain

referred pain

pain perceived as arising in one area when a different area is receiving the painful stimulus

merkel discs are located

in the skin

the hair follicle receptor is a receptor for

light touch

which has the smallest two point threshold

lips and/or fingertips

what is a kind of receptor that does not adapt

pain receptors

referred pain is

the phenomenon of perceiving pain on one area of the body when another area is actually receiving the painful stimulus

what type of receptor responds to the physical deformation of its cell membrane

mechanoreceptors

exteroreceptors

receptors found close to body surface and react to stimuli in the external environment

lamellar corpuscles respond to

deep pressure and vibrations

when a stimulus is applied for a prolonged period the rate of receptor discharge slows and conscious awareness of the stimulus declines

adaptation

What law states that the pressure of a given quantity of gas is inversely proportional to its volume?

boyles law

The volume of gas inspired or expired in a quiet respiration cycle is the

tidal volume

The total amount of gas in the lungs after a maximum inspiration is the

total lung capacity

The pressure that forms between the two layers of the pleura is called

intrapleural pressure

air pressure within the alveoli is called

intrapulmonary pressure

amount of air left in lungs after forceful expiration is called

residual volume

According to Henry's law, the amount of gas that will dissolve in blood plasma or any other liquid is determined by all of the following factors, except the

pH of liquid

What does a right shift in the oxygen dissociation curve indicate about the binding of oxygen to hemoglobin?

increased oxygen unloading

what is the direction of diffusion of gases at the alveoli of the lungs

oxygen into blood, carbon dioxide out of blood

what is the sum of the residual and the expiratory reserve volume

functional residual capacity

sum of partial pressures of nitrogen, oxygen, argon, carbon, etc

atmospheric pressure