Module 2 Quiz (synapses)

Which terms refers to a chemical that binds to another chemical?​ ​ligand ​vesicle ​electrolyte ​autoreceptor

ligand

A graded depolarization is known as an ____.​ ​IPSP ​EPIP EPSP ​ESPN

EPSP

The primary difference between an EPSP and an action potential is that ____.​ ​the magnitude of an action potential decreases as it travels along the membrane ​EPSPs occur without sodium ions entering the cell ​action potentials are always hyperpolarizations EPSPs are subthreshold events that decay over time and space

EPSPs are subthreshold events that decay over time and space

Which statement is TRUE about the spontaneous firing rates of neurons?​ ​EPSPs decrease the frequency. ​One EPSP equals the effect of two IPSPs. ​EPSPs increase the frequency. ​IPSPs increase the frequency.

EPSPs increase the frequency

A temporary hyperpolarization is known as an ____.​ ​EPSP ​ISPS ​EPIP ​IPSP

IPSP

What is the primary difference between temporal summation and spatial summation?​ ​Only spatial summation can produce an action potential. ​Spatial summation alters the response of more than one postsynaptic cell. Spatial summation depends on contributions from more than one sensory neuron. ​Temporal summation produces a hyperpolarization instead of a depolarization.

Spatial summation depends on contributions from more than one sensory neuron

The circuit from sensory neuron to muscle response is called ____.​ ​flexion a reflex arc ​extension ​a synapse

a reflex arc

The basic building blocks for the majority of neurotransmitters are ____.​ ​sugars ​nitric oxide ​carbohydrates amino acids

amino acids

"Second messengers" carry their messages to ____.​ ​the presynaptic membrane ​the surrounding glia areas within the postsynaptic cell ​areas within the presynaptic cell

areas within the postsynaptic cell

"Transporter" proteins transport neurotransmitters ____.​ ​to the appropriate receptor sites ​across the synapse back to the presynaptic neuron ​across the synapse to the postsynaptic neuron back into the presynaptic neuron

back into the presynaptic neuron

A metabotropic synapse, by way of its second messenger, ____.​ ​can influence activity in much of the presynaptic cell can influence activity in much or all of the postsynaptic cell ​has effects localized to one point on the membrane ​has minimal effect on the postsynaptic cell

can influence activity in much or all the postsynaptic cell

You are eating a food containing tryptophan. What can you consume with it to increase its entry to the brain?​ ​phenylalanine ​fats ​thiamine ​carbohydrates

carbohydrates

Neuropeptides are synthesized in the ____.​ cell body ​dendrites ​presynaptic terminal ​postsynaptic terminal

cell body

Which process will most likely result in an IPSP?​ ​sodium ions entering the cell ​chloride ions leaving the cell ​chloride ions entering the cell ​potassium ions entering the cell

chloride ions entering the cell

Loewi demonstrated that synapses operate by the release of chemicals by ____. ​applying adrenaline directly to the heart muscle ​measuring the speed of a dog's reflexes while the dog was under the influence of various drugs ​applying an extract of marijuana in eye drops and discovering that it dilated the pupils collecting fluid from a stimulated frog's heart, transferring it to another frog's heart, and measuring that heart rate

collecting fluid from a stimulated frog's heart, transferring it to another frog's heart, and measuring that heart rate.

A hormone is a chemical that is ____.​ ​secreted by a gland to the outside world ​conveyed by the blood to other organs, whose activity it influences ​capable of activating or inhibiting muscle fibers ​a feedback message from the postsynaptic neuron to the presynaptic neuron

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

Activation of autoreceptors tends to ____.​ ​stimulate GABA release ​increase further neurotransmitter release ​increase sodium-potassium pump activity decrease further neurotransmitter release

decrease further neurotransmitter release

An EPSP is to ____ as an IPSP is to ____.​ depolarization; hyperpolarization ​temporal summation; spatial summation ​spatial summation; temporal summation ​hyperpolarization; depolarization

depolarization; hyperpolarization

The primary method for disposal of peptide neurotransmitters is ____.​ ​reuptake by the presynaptic neuron ​diffusion ​inactivation ​reuptake by the postsynaptic neuron

diffusion

COMT and MAO are ____.​ ​the inactive fragments of catecholamines ​enzymes that make catecholamines enzymes that convert catecholamines into inactive chemicals ​neurotransmitters in the same group as serotonin

enzymes that convert catecholamines into inactive chemicals

Depolarization is to ____ as hyperpolarization is to ____.​ ​decreasing the threshold; increasing the threshold ​increasing the threshold; decreasing the threshold ​inhibition; excitation excitation; inhibition

excitation; inhibition

A neuron excretes neurotransmitters through its membrane by a process called ____.​ ​reuptake ​synaptic diffusion ​endocytosis ​exocytosis

exocytosis

The anterior pituitary is composed of ____ and the posterior pituitary is composed of ____.​ ​neural tissue; neural tissue ​neural tissue; glandular tissue glandular tissue; neural tissue ​glandular tissue; glandular tissue

glandular tissue; neural tissue

Vesicles are located ____.​ ​outside of the neuron in the extracellular fluid ​in dendrites ​in presynaptic terminals ​in postsynaptic terminals

in presynaptic terminals

In a reflex arc, the coordination between contraction of certain muscles and relaxation of others is mediated by ____.​ ​motor neurons ​interneurons ​glial cells ​sensory neurons

interneurons

The main advantage of a neuron releasing more than one neurotransmitter is that:​ ​if it runs out of one, it has others ​it can release one from the axon's terminal and one from another location along the axon ​it can release different transmitters on different occasions ​it can send more complex messages

it can send more complex messages

What happens to acetylcholine after it attaches to a receptor on the postsynaptic cell?​ ​It continues to stimulate the postsynaptic neuron until replaced by another neurotransmitter. ​It is metabolized by the postsynaptic cell as a source of energy. ​It is reabsorbed intact by the presynaptic cell. ​It is broken down into two components.

it is broken down into two components

The "spontaneous firing rate" of a neuron refers to ____.​ ​the velocity of its action potentials under normal conditions ​its resting potential ​its rate of energy consumption its rate of producing action potentials even when it is not stimulated

its rate of producing action potentials even when it is not estimulated

Ionotropic effects ____.​ ​enhance the reabsorption of neurotransmitters ​hyperpolarize the postsynaptic membrane ​depolarize the postsynaptic membrane ​may depolarize or hyperpolarize the postsynaptic membrane

may depolarize or hyperpolarize the postsynaptic membrane

Spatial summation refers to ____.​ ​multiple weak stimulations that occur in rapid succession ​an increase in the strength of action potentials after repeated stimulation multiple weak stimulations that occur at the same time ​a decrease in responsiveness after repeated stimulation

multiple weak stimulation that occur at the same time

In addition to influencing other neurons, ____ increases blood flow to a specific area of the brain.​ nitric oxide ​acetylcholine ​endorphins ​glycine

nitric oxide

Which neurotransmitter is released by stimulated neurons to dilate the blood vessels?​ ​glycine ​endorphins ​acetylcholine nitric oxide

nitric oxide

Ionotropic effects are characterized by ____.​ ​inhibitory effects only rapid and short-lived effects ​excitatory effects only ​rapid and long lasting effects

rapid and short-lived effects

Which pattern of post-synaptic excitation will most likely result in an action potential?​ ​large number of simultaneous IPSPs ​rapid sequence of IPSPs rapid sequence of EPSPs ​large number of simultaneous IPSPs and EPSPs

rapid sequence of EPSPs

The effect of a neurotransmitter on a postsynaptic neuron is determined by the ____.​ ​speed the action potential traveled down the axon ​receptors on the postsynaptic membrane ​distance between the synapse and the cell body ​number of branches of the presynaptic axon

receptors on the postsynaptic membrane

To measure temporal summation in single cells, researchers ____.​ ​insert an microelectrode into the scalp ​collect sodium and potassium ions from nearby glial cells ​attach electrodes to the scalp ​record depolarizations of the postsynaptic neuron

record depolarizations of the postsynaptic neuron

What is the proper ordering of a reflex arc?​ ​sensory neuron, motor neuron, interneuron. ​motor neuron, interneuron, sensory neuron. ​motor neuron, sensory neuron, interneuron. sensory neuron, interneuron, motor neuron.

sensory neuron, interneuron, motor neuron

The amino acid tryptophan is the precursor to which neurotransmitter?​ serotonin ​nitric oxide ​endorphin ​dopamine

serotonin

Even at rest, most neurons have periodic production of action potentials, known as the ____.​ spontaneous firing rate ​excitatory firing rate ​all-or-none law ​law of compensation

spontaneous firing rate

A certain weak stimulus produces no reflexive response, but a rapid repetition of that stimulus may produce such a response. What is this phenomenon called?​ ​temporal summation ​saltatory conduction ​spatial summation ​synaptic combination

temporal summation

What is the synaptic cleft?​ ​a packet that stores neurotransmitter molecules for release the gap between the presynaptic neuron and the postsynaptic neuron ​the long-term storage location for calcium ions ​a subthreshold depolarization mechanism

the gap between the presynaptic neuron and the postsynaptic neuron

What happens when a neurotransmitter is released by a presynaptic cell?​ ​It causes calcium to rush into the postsynaptic neuron. ​It causes calcium to rush into the presynaptic neuron. The neurotransmitter passively spreads across the synaptic cleft. ​The neurotransmitter is actively transported across the synaptic cleft.

the neurotransmitter passively spreads across the synaptic cleft.

What causes an EPSP?​ ​the deactivation of stress response pathways ​the deactivation of cytoplasmic enzymes the opening of sodium channels ​the opening of potassium channels

the opening of soidum channels

Sherrington deduced that transmission at a synapse must be slower than conduction along an axon. This was based on what kind of evidence?​ ​the speed of reflexive responses ​drugs that increase or inhibit activity at synapses ​temporal summation ​differences in diameter between axons and dendrites

the speed of reflexive responses

Which statement is TRUE of EPSPs?​ ​They can be either excitatory or inhibitory. ​They occur because potassium gates open. They decay over time and space. ​They work in pairs to produce an action potential.

they decay over time and space