QUIZ 6

Question 1

Regardless of the strength of a subsequent stimulus, an action potential cannot be generated during the relative refractory period.
(T/F)

Answer 1

FALSE

Question 2

Excitatory post-synaptic potentials (EPSPs) are always depolarizing.
(T/F)

Answer 2

TRUE

Question 3

Action potentials are conducted without decrement between neurons.
(T/F)

Answer 3

FALSE

Question 4

Graded potentials have a threshold.

T/F

Answer 4

FALSE

Question 5

The Na+ - K+ ATPase pump located in the cell membrane exchanges three (3) Na+ out of and two (2) K+ into the cell.
(T/F)

Answer 5

TRUE

Question 6

In a muscle stretch receptor, the muscle spindles are found in the extrafusal fibers.
(T/F)

Answer 6

FALSE

Question 7

During the upslope of the action potential, once threshold is passed, there is a dramatic increase in Na+ conductance out of the cell.
(T/F)

Answer 7

FALSE

Question 8

The hyperpolarization found in a typical action potential is caused by the delay in closing the voltage-gated K+ channels.
(T/F)

Answer 8

TRUE

Question 9

The nodes of Ranvier on an unmyelinated axon permit rapid transmission of the action potential.
(T/F)

Answer 9

FALSE

Question 10

In the axon terminal, the action potential first stimulates the opening of the voltage-gated Ca++ channels, permitting rapid influx of Ca++.
(T/F)

Answer 10

TRUE

Question 11

An action potential will respond to very strong stimulus by increasing the amplitude of action potential.
(T/F)

Answer 11

FALSE

Question 12

When neurotransmitters are released from the pre-synaptic neuron, they always stimulate an action potential in the post-synaptic neuron.
(T/F)

Answer 12

FALSE

Question 13

Grade potentials can be summed.

T/F

Answer 13

TRUE

Question 14

The closure of the Na+ voltage gated channels and the opening of the K+ voltage gated channels begins the repolarization portion of the action potential.
(T/F)

Answer 14

TRUE

Question 15

At the axon terminal, neurotransmitters are released into synaptic cleft by exocytosis.
(T/F)

Answer 15

TRUE

Question 16

After neurotransmitters are released into the synapse, they bind to the specific ligand gated channel causing an influx of Na+ ions into the cell resulting in an inhibitory post synaptic potential (IPSP)
(T/F)

Answer 16

FALSE

Question 17

The shape of the action potential can differ in different excitable tissues.
(T/F)

Answer 17

TRUE

Question 18

The duration of an action potential in the neurons depends on the strength of the stimulus.
(T/F)

Answer 18

FALSE

Question 19

The Na+K+ ATPase Pump is not involved in the establishment of the resting membrane potential.
(T/F)

Answer 19

FALSE

Question 20

In a neuron at rest, both the Na+ and K+ leak channels are closed.
(T/F)

Answer 20

FALSE