Practice Q's - Ch 2

Question 1

Charles S Sherrington was the first to infer properties of

Answer 1

synapses.

Question 2

Sherrington studies _____ which are automatic muscular responses to stimuli.

Answer 2

reflexes

Question 3

Joe is in the lab drawing illustrations of neurons in her lab notebook. She labelled the specialized area between two neurons as the _______

Answer 3

synapse.

Question 4

On the basis of what evidence were the properties of synapses first inferred?

Answer 4

behavioural observations

Question 5

the circuit from sensory neuron to muscle response is called ____

Answer 5

a relfex arc.

Question 6

Mary is studying the refelx arc for a quiz. In her notes she wrote down that the proper order is

Answer 6

sensory, inter, motor neuron.

Question 7

why is the speed of conduction through a reflex arc slower than the speed of conduction of an action potential along an axon?

Answer 7

transmission between neurons at synapses is slower than along axons.

Question 8

Sherrington deduced that transmission at a synapse must be slower than conduction along an axon. This was based on what kind of evidence?

Answer 8

the speed of reflexive responses

Question 9

Dr. Andrus studies relfexes and has demonstrated that a certain reflex doesnt occur if there is a single stimulus. He found that there needs to be __________ for the reflex to occur.

Answer 9

temporal summation

Question 10

Sherrington found that repeated stimuli within a brief time have a cumulative effect. He referred to this as _____

Answer 10

temporal summation.

Question 11

temporal summation most likely occurs with

Answer 11

rapid succession of threshold excitation.

Question 12

Charles Sherrington would most likely agree with which statement about reflexes?

Answer 12

repeated stimuli occurring within a brief time can have a cumulative effect.

Question 13

to measure temporal summation in single cells, researchers ________

Answer 13

record depolarizations of the postsynaptic neuron.

Question 14

Lin is working in the lab to generate an EPSP, which is a __________

Answer 14

graded depolarization.

Question 15

which statement is true of EPSP?

Answer 15

they decay over time and space.

Question 16

the neuron that receives the message is called the _________ neuron.

Answer 16

postsynaptic

Question 17

Prof Kinsley is lecturing on EPSPs and action potentials. She tells the class that

Answer 17

EPSPs are decremental and action potentials are not.

Question 18

Depolarization is to _________ as hyperpolarization is to ___________

Answer 18

excitation; inhibition.

Question 19

Brock is working in the lab and has been able to demonstrate that

Answer 19

the opening of sodium channels causes an EPSP

Question 20

which process indicates spatial summation?

Answer 20

present two or more weak stimuli at the same time.

Question 21

spatial summation refers to

Answer 21

multiple weak stimulations that occur at the same time.

Question 22

What is the primary difference between temporal summation and spatial summation?

Answer 22

spatial summation depends on contributions from more than one sensory neuron.

Question 23

Kate is in the lab working ans was able to produce a reflexive response by stimulating several different locations all at one time. She successfully demonstrated ______ summation.

Answer 23

spatial

Question 24

what do temporal summation and spatial summation have in common?

Answer 24

both enable a reflex to occur in response to weak stimuli.

Question 25

temporal summation is to _______ as spatial summation is to ___________.

Answer 25

time; location.

Question 26

Jan is in the lab trying o produce action potential in her cultured neurons? What is most likely to work?

Answer 26

using electrical stimulation to produce a rapid sequence of EPSPs.

Question 27

when a vertebrate animal contracts the flexor muscles of a leg, it relaxes the extensor muscles of the same leg. Sherrington considered this evidence for the existence of _______.

Answer 27

inhibitory messages.

Question 28

what ordinarily prevents extensor muscles from contracting at the same time as flexor muscles?

Answer 28

inhibitory synapses in the spinal cord.

Question 29

_______ in the ________ help coordinate contraction of certain muscles and relaxation of others.

Answer 29

motor neurons; peripheral nervous system.

Question 30

inhibitory synapses on a neuron?

Answer 30

hyper-polarize the postsynaptic ell.

Question 31

a temporary hyperpolarization is known as an

Answer 31

IPSP.

Question 32

Tam is working in the lab trying to produce an IPSP in her cultures neurons. what should she do?

Answer 32

encourage chloride ions to enter the cell.

Question 33

Increased permeabilty to which type of ion would most likely result in an IPSP?

Answer 33

potassium.

Question 34

an IPSP represents

Answer 34

a temporary hyper-polarization.

Question 35

In order to produce an IPSP, there needs to be an increase in permeability for _______

Answer 35

chloride.

Question 36

an EPSP is to __________ as an IPSP is to _________.

Answer 36

depolarization, hyper-polarization.

Question 37

Even at rest, most neurons have periodic production of action potentials, known as the _________

Answer 37

spontaneous firing rate.

Question 38

the "decision" for a neuron to fire is determined by the

Answer 38

ratio of EPSP to IPSPs.

Question 39

the "spontaneous firing rate" of a neuron refers to

Answer 39

its rate of producing action potentials even when it is not stimulated.

Question 40

_______ increases the frequency of the spontaneous firing rate.

Answer 40

EPSP

Question 41

what determines whether a neuron has an action potential?

Answer 41

the combined effects of EPSPs and IPSPs.

Question 42

which one of Sherringtons inferences about the synapse was wrong?

Answer 42

transmission at the synapse is primarily an electrical process.

Question 43

neuroscienctists first understood that synapses use chemicals to communicate because Dr.Loewi _________

Answer 43

stimulated a frogs heart that was in a fluid bath and then used just the fluid to stimulate a second heart.

Question 44

the research that firmly established synaptic communication as chemical was ____________

Answer 44

Loewi's transfer of fluid from stimulated frog hearts.

Question 45

which category of chemicals included adenosine and several of its derivatives?

Answer 45

Purines

Question 46

on advantage of nitric oxide is that is

Answer 46

can be made by neurons effieciently

Question 47

if Vonnie's body needed to dilate her blood vessels, it would release

Answer 47

nitric oxide.

Question 48

In addition to influencing other neurons, __________ increases blood flood to a specific area of the brain.

Answer 48

nitric oxide.

Question 49

what provides the building blocks for synthesizing nearly all neurotransmitters?

Answer 49

proteins found in the diet.

Question 50

neurotransmitters are synthesized from

Answer 50

amino acids

Question 51

____________, ___________, and _________ are catecholamines

Answer 51

E, NE, DA

Question 52

What makes nitric oxide unique among neurotransmitters?

Answer 52

It is a gas.

Question 53

What do dopamine, norepinephrine, and epinephrine share in common?

Answer 53

They are all synthesized from the same amino acids.

Question 54

Riva is unable to eat eggs, milk, and peanuts. She might have altered levels of _____ as a result.

Answer 54

acetylcholine

Question 55

The amino acid tryptophan is the precursor to which neurotransmitter?

Answer 55

Serotonin

Question 56

73. Lita has just eaten a lot of soy, which contains tryptophan. What should she try to consume less of to potentially increase tryptophan’s entry to the brain?

Answer 56

a. Phenylalanine

Question 57

Dopamine and norepinephrine are classified as ____.

Answer 57

catecholamines

Question 58

Insulin increases the entry of tryptophan into the brain by _________

Answer 58

causing certain competing amino acids to enter other cells, outside the brain

Question 59

Luis is studying for a quiz on neurotransmission. He wrote in his notes that neurotransmitters are typically stored in _____ in the _____ neuron.

Answer 59

vesicles; presynaptic

Question 60

Neuropeptides are synthesized in the ____.

Answer 60

cell body

Question 61

Although slower than an action potential, synaptic transmission is still relatively fast because ____.

Answer 61

the synaptic cleft is very narrow

Question 62

Vesicles are located ____.

Answer 62

in presynaptic terminals

Question 63

Neurotransmitters are released from the | presynaptic neuron when the action potential reaches the terminal and opens ______ channels.

Answer 63

calcium

Question 64

When an action potential reaches the end of an axon, the depolarization causes what ionic movement in the presynaptic cell?

Answer 64

Calcium into the cell

Question 65

An action potential causes the release of neurotransmitters by ____.

Answer 65

opening calcium pores in the membrane

Question 66

A neuron excretes neurotransmitters through its membrane by a process called ____.

Answer 66

exocytosis

Question 67

Exocytosis is the process by which neurotransmitters are ____.

Answer 67

released from the presynaptic neuron

Question 68

What is the synaptic cleft?

Answer 68

The gap between the presynaptic neuron and the postsynaptic neuron

Question 69

What happens when a neurotransmitter is released by a presynaptic cell?

Answer 69

The neurotransmitter passively spreads across the synaptic cleft.

Question 70

In general, a single neuron releases ____ neurotransmitter(s) and can respond to ____ neurotransmitter(s).

Answer 70

several; many

Question 71

The main advantage of a neuron releasing more than one neurotransmitter is that:

Answer 71

it can send more complex messages

Question 72

The effect of a neurotransmitter on a postsynaptic neuron is determined by the ____.

Answer 72

receptors on the postsynaptic membrane

Question 73

A receptor can directly open a channel and thereby exert a(n) ____ effect, or it can produce slower but longer ____ effect.

Answer 73

ionotropic; metabotropic

Question 74

Most of the brain’s excitatory ionotropic synapses release ____ while the inhibitory ionotropic synapses release ____.

Answer 74

glutamate; GABA

Question 75

Glutamate opens sodium gates, enabling sodium ions to enter the postsynaptic cell. What type of effect is this?

Answer 75

Ionotropic

Question 76

Ionotropic effects ____.

Answer 76

may depolarize or hyperpolarize the postsynaptic membrane

Question 77

Ionotropic effects are characterized by ____.

Answer 77

rapid and short-lived effects.

Question 78

Which terms refers to a chemical that binds to another chemical?

Answer 78

Ligand

Question 79

Raylene is studying for an exam on neurotransmission. She wrote in her notes that one difference between ionotropic and metabotropic effects is that _____.

Answer 79

metabotropic effects are slower and longer lasting

Question 80

Which process is more typical of a metabotropic effect than an ionotropic effect?

Answer 80

Producing long-lasting effects on the post-synaptic cell

Question 81

Receptor molecules for neurotransmitters that exert metabotropic effects are proteins that bind to ____ outside the membrane, and attach to ____ inside the membrane.

Answer 81

neurotransmitters; G-proteins

Question 82

“Second messengers” carry their messages to ____.

Answer 82

areas within the postsynaptic cell

Question 83

A metabotropic synapse, by way of its second messenger, ____.

Answer 83

can influence activity in much or all of the postsynaptic cell

Question 84

Many neurons release neuropeptides mostly from the ____.

Answer 84

dendrites

Question 85

A hormone is a chemical that is ____.

Answer 85

conveyed by the blood to other organs, whose activity it influences

Question 86

Hormones exert their effects ____.

Answer 86

similarly to metabotropic neurotransmitters

Question 87

The anterior pituitary is composed of ____ and the posterior pituitary is composed of ____.

Answer 87

glandular tissue; neural tissue

Question 88

Releasing hormones are synthesized in the ____ and released in the ____.

Answer 88

hypothalamus; anterior pituitary

Question 89

Adrenocorticotropic hormone (ACTH) controls secretions of the ____.

Answer 89

adrenal gland

Question 90

What is the function of the enzyme acetylcholinesterase?

Answer 90

it breaks acetylcholine down into components for recycling.

Question 91

What happens to acetylcholine after it attaches to a receptor on the postsynaptic cell?

Answer 91

It is broken down into two components.

Question 92

Dr. Edmonson is working in the lab with cultured neurons. He applies a drug that inhibits acetylcholinesterase. What does he expect to have occur?

Answer 92

Acetylcholine will remain active in the synapse longer.

Question 93

Reuptake is an alternative to which other process?

Answer 93

Breaking down neurotransmitters via an enzymatic process

Question 94

“Transporter” proteins transport neurotransmitters ____.

Answer 94

back into the presynaptic neuron

Question 95

COMT and MAO are ____.

Answer 95

enzymes that convert catecholamines into inactive chemicals

Question 96

The primary method for disposal of peptide neurotransmitters is ____.

Answer 96

diffusion

Question 97

Professor Leclair is giving a lecture on autoreceptors. She tells the class that _____.

Answer 97

activated autoreceptors decrease neurotransmitter release

Question 98

Autoreceptors monitor the ____.

Answer 98

amount of neurotransmitter released