Neuro 5

Question 1

What is the purpose of the refractory period?

Answer 1

ensures an AP travels in one direction and limits rate at which signals can be transmitted

Question 2

Two physical parameters that determine the velocity of APs

Answer 2

diameter of axon and resistance of axon to ion leakage

Question 3

conduction velocity is more rapid in…..

Answer 3

myelinated axons because decreased ion leak with high resistance membranes

Question 4

saltatory conduction

Answer 4

conduction occurs from node to node

Question 5

__________ axons are larger diameter axons that ____________ axons.

Answer 5

myelinated, unmyelinated

Question 6

what can alter electrical activity?

Answer 6

chemical factors (local anesthetics) and changes in extracellular conc of cellular ions

Question 7

the conc. gradient for K+ is crucial in setting…

Answer 7

the resting membrane potential

Question 8

normokalemia

Answer 8

above threshold; AP

Question 9

hyperkalemia

Answer 9

stimulus that would normally be sub threshold can trigger an AP

Question 10

hypokalemia

Answer 10

neuron less likely to fire an AP that would normally be above threshold

Question 11

cells communicate at…

Answer 11

synapses

Question 12

synapses found on…

Answer 12

dendrites, soma and even on axon and axon terminals

Question 13

electrical synapses

Answer 13

ions flow from cell directly to the next

Question 14

chemical synapses

Answer 14

majority in nervous system

Question 15

neurocrine

Answer 15

a chemical substance released from neurons used for communication

Question 16

types of neurocrines

Answer 16

neurotransmitters, neuromodulators, and neurohormones

Question 17

neurotransmitters

Answer 17

chemical released that acts on postsynaptic cell in close vicinity and causes a rapid response

Question 18

neuromodulator

Answer 18

chemical released that acts on postsynaptic cell in close vicinity and causes a slow response

Question 19

neurohormones

Answer 19

secreted into the bloodstream and act on targets throughout the body

Question 20

two categories of neurocrine receptors

Answer 20

ionotropic receptors and metabotropic receptors

Question 21

inotropic receptors

Answer 21

mediate fast postsynaptic responses (neurotransmitters) through ligand gated ion channels

Question 22

metabotropic receptors

Answer 22

linked to a three part membrane transducer (g-protein) and mediates slower responses (neuromodulators)

Question 23

metabotropic receptors interact with…

Answer 23

ion channels or with a membrane bound enzyme