outcome 7 chapter 11 nervous system

Question 1

a change in the resting membrane potential has the following characteristics: non-propagated, graded, can summate. this type of change can…
a. be a consequence of an increase in the permeability to na+
b. be a local potential and a consequence of an increase in the permeability to na+
c. result in repolarization
d. be an action potential
e. be a local potential

Answer 1

b. be a local potential and a consequence of an increase in the permeability to na+

Question 2

a decrease in the number of voltage-gated ca2+ ion channels in the presynaptic terminal would
a. have no effect on transmission across the synapse
b. increase in exocytosis
c. enhance transmission across the synapse
d. alter receptors on the postsynaptic
e. reduce or inhibit transmission across th synapse

Answer 2

e. reduce or inhibit transmission across the synapse

Question 3

a local anaesthic such as novocine decreases membrane permeability to na+ the use of this anesthetic will
a. cause cl- to enter cells instead of na +
b. enhance the development of epsp’s
c. cause membrane potential to move closer to threshold
d. depolarize the cell
e. block sensory input into the cns

Answer 3

e. block sensory input into the cns

Question 4

a local potential
a. does not occur until threshold
b. transmits information from one cell to another
c. increases or decreases in direct proportion to the stimulus strength
d. might be a depolarization event but cannot be a hyperpolarization
e. does not alter resting membrane potential

Answer 4

c. increase or decreases in direct proportion to the stimulus strength

Question 5

a myelin sheath is composed of primarily
a. protiens
b. glycoproteins
c. polysaccharides
d. lipids
e. carbohydrates

Answer 5

d. lipids

Question 6

a neuron is recieiving a stimulus which gets stronger and stronger the result is __
a. amplitude of the action potential increase
b. frequency of occurrence of action potentials increase
c. resonance of action potentials increase
d. height of the action potentials increase
e. duration of the action potential increases

Answer 6

b. frequency of occurrence of the action potential increases

Question 7

a neuron that conducts pain sensations to the central nervous system would be classified as a/an __
a. interneuron
b. association neuron
c. efferent neuron
d. sensory or afferent neuron
e. motor neuron

Answer 7

d. sensory or afferent neuron

Question 8

a neuro transmitter is released at a synapse which of the following occurs late
a. neurtotransmitter binds with the receptor on the post synaptic membrane
b. neutransmitters flows rapidly across the synaptic cleft
c. synaptic vesicles realease neurotransmitter by exocytosis
d. calcium ions enter the presynaptic terminal
e. an action potential is produces in the postsynapitc membrane

Answer 8

e. an action optential is produced in the postsynaptic membrane

Question 9

a person who has seizures might habe a deficit of which of the following
a. serotonini
b. histamine
c. gaba
d. glutamate
e. dopamine

Answer 9

c. gaba

Question 10

a stimulus either causes an action potentail or it doesn’t, this is called ___
a. local response
b. a relative refractory response
c. an all-or-none response
d. a latent period response
e. a graded response

Answer 10

c. an all or none response

Question 11

a substance is found to have the same effect as a acetylcholinesterase but acts at a much faster rate, whateffect would this substance have at a cholinergic synapse
a. it would enhance synaptic communication by increasing the post synaptic cells sensitivity to ach
b. it would greatly reduce synaptic communication by depleting ach levels in the synaptic cleft
c. it would enhance synaptic communication by ach in the synaptic cleft
d. it reduce synaptic communication by destroying ach receptors on the post-synaptic membrane

Answer 11

b. it would greatly reduce synaptic communication by depleting ach levels in the synaptic cleft

Question 12

action potentials are conducted more rapidly when transimission is
a. on a small diameter axon
b. from node to node on a myelinated axon
c. from internode to internode
d. from internode to node on a myelinated axon
e. on an unmyelinated

Answer 12

b. from node to node on a myelinated

Question 13

action potentials at a chemical synapse
a. travel from synaptic terminal to presynaptic membrane
b. stop at the presynaptic terminal and are blocked on the postsynaptic membrane
c.. travel back and forth from presynaptic terminal to postsynaptic membrane
d. travel from postsynaptic membrane to presynaptic terminal
e. travel from presynaptic terminal to postsynaptic membrane

Answer 13

e. travel from presynaptic terminal to postsynaptic membrane

Question 14

all of the following are typical characteristics of neurotransmitter except
a. they bind to specific receptors on the postysnaptic cell
b. they are synthesized by a presynaptic neuron
c. they are released into the bloodstream before reashing the postsynaptic cell
d. they alter the physiology of the postsynaptic cell
e. they are released in response to stimulation

Answer 14

c. they are released into the bloodstream before reashing the postsynaptic cell

Question 15

an action potential
a. is an example of negative feedback
b. occurs when the local potential reaches threshold level
c. cannot transmit information
d. has no repolarization phase
e. propogates across the plasma membrane in a decremental fashion

Answer 15

b. occurs when the local potential reaches threshold level

Question 16

an inhibitory local potential causes which of the following
a. hyperpolarization of the plasma membrane
b. drifting of the membrane potential towards the resting membrane potential
c. depolarization of the plasma membrane
d. neutralization of the plasma membrane
e. repolarization of the plasma membrane

Answer 16

a. hyperpolarization of the plasma membrane

Question 17

an inhibjitory postsynaptic potential can result from the __-
a. influx of cl-
b. outflow of k+
c. both influx of cl- and outflow of k+ are correct
d. influx of ca2+
e. influx of na+

Answer 17

c. both influx of cl- and outflow of k+ are

Question 18

an inhibjitory postsynaptic potential is inhibitory because it
a. prevents ca2_ entry into the presynaptic terminal
b. depolarizes the postsyanptic membrane
c. hyperpolarizes the postsyanptic membrane
d. reduces the amount of neurotransmitter released by the presynaptic terminal
e. changes the threshold of the neuron

Answer 18

c. hyperpolarizes the postsyanptic membrane

Question 19

axons
a. do not have a resting membrane potential
c. contain the nucleus
d. do not have a trigger zone
e. have a distal portion that branches to form the presynaptic terminals

Answer 19

e. have a distal portion that branches to form the presynaptic terminals

Question 20

axons contain ____
a. nissl bodies
b. the trigger zone
c. foot processes
d. the rough endoplasmic reticulum
e. the soma

Answer 20

b. the triggerzone

Question 21

chemical synapses are characterized by
a. connectiions at connect the pre and postsyanptic terminals of the cells
b. the absence of gap junctions
c. receptors located only on the presynaptic terminal
d. the release of neurotransmitter by the presyanptic terminal
e. the preseence of receptors for neurotransmittters on the presynaptic terminal

Answer 21

d. the release of neurotransmitter by the presyanptic terminal

Question 22

clusters of gray matter deep within the brain are called___
a. ganglie
b. cortices
c. nuclei
d. nerves

Answer 22

c. nuclei

Question 23

damage to a postsynaptic membrane would
a. increase neurotransmitter release
b. destroy vesicles containing neurotransmitter
c. decrease the release of neurotransmitter
d. interfere with the ability to respond to neurotransmitter
e. increase neurotransmitter production

Answer 23

d. interfere with the ability to respond to neurotransmitter

Question 24

dendrites
a. conduct action potnetials away from the cell body
b. are generally long and unbranched
c. are the input part of the neurond
d. contain the trigger zone
e. form synapses with microgilia

Answer 24

c. are the input of part of the neuron

Question 25

depolarization of the nerve plasma membrane occurs whe there is a rapid influx of a. na+ b. ca2+ d. cl- e. proteins

Answer 25

a. na+

Question 26

during the absolute refractory period, the cell a. generates many local potentials b. responds to even weak stimuli c. reverses the direction of the action potential d. is very sensitive e. is insensitive to further stimulation

Answer 26

e. is insensitive to further stimulation

Question 27

for the resting membrane potential increasing the na+ concentration in the ecf results in a. hypoplarization b. hyperpolarization c. little chane in membrane potential d. there is not enough information to determine the results e. depolarization

Answer 27

c. membrane potential

Question 28

frank has a microbial infection attackin his brain which cell type would you expec to proliferate and be most active during this time a. oligo dendrecytes b. schwann cells c. ependymal cells d. microglia e. astrocytes

Answer 28

d. microglia

Question 29

gap junctions are functionally ____ synapses a. neuromuscular b. chemical c. electrical d. potential e. intracellular

Answer 29

c. electrical

Question 30

gaps or interruptions in the myelin sheath are called a. tight junctions b. neurofilaments c. gap junctions d. internodes e. nodes of ranvier

Answer 30

e. nodes of ranvier

Question 31

gray matter on the surface of the brain is called a. a tract b. a nucleus c. the cortex d. a ganglion

Answer 31

c. the cortex

Question 32

groups of related nerve cell bodies located outside of the central nervous system are calles a. nerved b. plexus c. tracts d. ganglia

Answer 32

d. ganglia

Question 33

hydrocephaly is a condition whereby cerebrospinal fluid accumulates around the brain, which supportive cells continue csp production despite it backing up in the subarachnoid space a. macrophages b. oligodendrocytes c. ependymal cells d. microglia e. astrocytes

Answer 33

c. ependymal cells

Question 34

identify the correct sequence of the structures as they are involved in activity at a chemical synapse a. presynaptic terminal; syanptic cleft; postsyanptic membrane b. presyantpic terminal; postsyanaptic membrane; synaptic cleft c. cynaptic cleft; presynaptic terminal; postsynatpic membrane d. postsynaptic membrane; synaptic cleft; presynaptic terminal

Answer 34

a. presynaptic terminal; syanptic cleft; postsyanptic membrane

Question 35

identify the statement taht best differentiates gray matter and white matter a. gray matter conssits of bundles of axons and white mater consists of groups of cell bodies and dendrites b. gray matter consists of cell bodies and dendrites, whereas white matter consists mostly of myelinated axons c. gray matter cells consist of all parts of nueros and white matter is mostly glia cells

Answer 35

b. gray matter consists of cell bodies and dendrites, whereas white matter consists mostly of myelinated axons

Question 36

identify the two functional subdivisions of the peripheral nervous system a. sympathetic division b. brain c. spinal cord d. motor division e. sensory division f. parasympathetic division

Answer 36

d. motor division, e. sensory division

Question 37

identify the type of synapse that includes a presynaptic clet and postsynaptic cell a. electrical b. neurotransmitter c. indirecy d. electrochemicale. e. direct

Answer 37

d. electrochemical

Question 38

if five action potentials arive at the same syanpsein very close succesion which of the following would occur a. spatial summations occurs b. hyperpolarization occurs c. depolraization occurs d. temporal summation occurs e. the direction of the action potential is reversed

Answer 38

d. temporal summation occurs

Question 39

if yo ucut bundles of axons and their myelin sheaths in the PNS yo ucut____ a. nuclei b. nerves c. ganglia d. gray matter e. nerve tracts

Answer 39

b. nerves

Question 40

in hyperpolarization a. the plasma membrane potentials becomes more positive b. the k+ tend to diffuse out of the cell c. k+ tend to diffuse out of the cell d. na+ enter the cell in large numbers e. the resting membrane potential moves closer to zero

Answer 40

c. k+ tend to diffuse out of the cell

Question 41

in order for local potnetials to trigger and action potential the membrane must reach a level called the a. threshold b. resting membrane potential c. maximum potentials d. spike potential

Answer 41

a. threshold

Question 42

low levels of ___ can have dire consequences of the functioning of neurons because fo itss role in membrane repolarization a. h+ b. k+ c. na+ d. cl-

Answer 42

b. k+

Question 43

multiple sclerosis is a neurological disorder in which myelin sheaths in the cns are destroyed. which of the following neurologlial cells is being damaged in multiple sclerosis a. oligodendrecytes b. ependymal cell c. astrocyte d. schwann cells e. microglia

Answer 43

a. oligodendrocyte

Question 44

nerve tissue of teh cns that is composed primarily of myelinated axon is referred to as ___ matter a. white b. dark. c. light d. gray

Answer 44

a. white

Question 45

neurons in the skin taht are ersponsible for detecting pain are a. bipolar b. multipolar c. pseudo unipolar d. apolar

Answer 45

c. pseudo unipolar

Question 46

neurotransmitters are releasd from the a. ca2+ channels b. presynaptic terminal c. epineurium d. synapitc cleft e. postsynaptic membrane

Answer 46

b. presynaptic terminal

Question 47

saltatory conduction of an action potential means that a. the whole axon depolaraizes at the same time b. once one action potential is creatd is moves down the axon c. an action potential is conducted from one node of ranvier to the next node d. one action potential stimulates the production of a new action potential at the adjacent site

Answer 47

c. an action potential is created, it moves down the axon

Question 48

schwann cells differ from oligodendrocytes in which of the following ways a. oligodendrocytes are found in the the pns; schwann cells are only found in the cns b. schwann cells form myelin; oligodendrocytes do not c. none of the choices are correct d. schwann cells form a myelin sheath around a portion of only one axon, while oligodendrocytes can surround portions of several axons e. schwann cells fomr sheaths around several axons, while oligodendrocytes form sheaths around only one axon.

Answer 48

d. schwann cells form a myelin sheath around a portion of only one axon, while oligodendrocytes can surround portions of several axons

Question 49

synaptic vesicles contain neurotransmitters and are present in the a. cell body b. trigger zone c. axolemma d. presynaptic terminals e. dendrites

Answer 49

d. presynaptic terminals

Question 50

the blood brain barrier a. rotects from toxic substances in the blood b. prohibits the transport of amino acids and glucose to the neurons c. permits passage of foreign substances from the blood of the neurons d does not prevent fluctuations in the composition of the blood from affecting the functions of teh brain e. prohibits the removal of waste materials from the neurons

Answer 50

a. protects neurons from toxic substances in the blood

Question 51

the central nervous sytem includes the a. crnaial nerves b. sensory receptors c. spinal cord d. ganglia e. spinal nerves

Answer 51

c. spinal cord

Question 52

the function of acetylsholinesterase is to a . open voltage gated na+ cahnnels b. brekadonw acetylcholine in the synapse c. metabolize norepinnephrine d. produce an ipsp on the postysnaptic membrane

Answer 52

b. brekadonw acetylcholine in the synapse