Session 3i

After a meal that was rich in the amino acid tryptophan, which neurotransmitter level would be increased the most? a. dopamine b. endorphin c. serotonin d. nitric oxide

c. serotonin

What determines whether a neuron has an action potential? a. only the number of EPSPs impinging on an axon b. only the number of IPSPs impinging on the dendrites c. the combined effects of EPSPs and IPSPs d. summation effects of IPSPs

c. the combined effects of EPSPs and IPSPs

Which of the following is NOT a catecholamine? a. Dopamine b. Epinephrine c. Norepinephrine d. Serotonin

d. Serotonin

The release of neurotransmitter from the presynaptic terminal is most dependent on the influx of what ion? a. sodium b. potassium c. chloride d. calcium

d. calcium

When an action potential reaches the end of an axon, the depolarization causes what ionic movement in the presynaptic cell? a. sodium out of the cell b. lithium out of the cell c. iron into the cell d. calcium into the cell

d. calcium into the cell

Dopamine and norepinephrine are classified as: a. second messengers. b. purines. c. proteins. d. catecholamines.

d. catecholamines.

Insulin increases the entry of tryptophan into the brain by: a. weakening the blood-brain barrier. b. converting tryptophan into a compound that more easily enters the brain. c. increasing metabolic activity only in those areas of the brain that use tryptophan. d. causing certain competing amino acids to enter other cells, outside the brain.

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

What stimulates dopamine release in the nucleus accumbens

gambling, sexual excitement, video games

build up of pressure in the brain and swelling of the head caused if the flow of CSF is blocked; can result in retardation

hydrosphillus

Inhibitory synapses on a neuron

hyper polarize the post- synaptic cell

a change in the resting potential from -70 mv to -73 mv is called

hyperpolarization

IPSP

hyperpolarize, stop an impulse

Chemicals release by a neuron onto a target with an excitatory or inhibitory effect are called

neutrotransmitters

a group of cells forming a cluster that can be identified with special stains to form a functional group is called a

nucleus

in the peripheral nervous system that myelinates axons

oliodendroglia

small neurotransmitter is synthesized

presynaptic

Why is the speed of conduction through a reflex arc slower than the speed of conduction of an action potential along an axon? a. Transmission between neurons at synapses is slower than along axons. b. The longer an axon, the slower its velocity. c. Interneurons have thicker axons than other neurons. d. There are greater amounts of myelin involved in the reflex arc.

a. Transmission between neurons at synapses is slower than along axons.

Exocytosis is the process by which neurotransmitters are: a. excreted into the synaptic cleft. b. synthesized. c. destroyed. d. secreted into synaptic vesicles.

a. excreted into the synaptic cleft.

An EPSP is a(n): a. graded depolarization. b. depolarization with a rebounding hyperpolarization. c. graded hyperpolarization. d. action potential in a reflex arc.

a. graded depolarization.

Nitric oxide's value is that it: a. increases blood flow to certain areas of the brain. b. restricts blood flow to certain areas of the brain. c. increases growth of microglia. d. decreases growth of microglia.

a. increases blood flow to certain areas of the brain.

High concentrations of all neurotransmitters, except for NO, are stored in the: a. presynaptic terminals. b. postsynaptic terminals. c. axon. d. cell body.

a. presynaptic terminals.

Which of the following patterns of post-synaptic excitation will most likely result in an action potential? a. rapid sequence of EPSPs b. rapid sequence of IPSPs c. large number of simultaneous IPSPs d. large number of simultaneous IPSPs and EPSPs

a. rapid sequence of EPSPs

Even at rest, most neurons have periodic production of action potentials, known as the: a. spontaneous firing rate. b. excitatory firing rate. c. all-or-none law. d. Dale's principle.

a. spontaneous firing rate.

What provides the building blocks for synthesizing all neurotransmitters? a. substances found in the diet b. breakdown products of DNA c. breakdown products formed from other transmitters d. methane and ethanol

a. substances found in the diet

Sherrington found that repeated stimuli within a brief time have a cumulative effect. He referred to this phenomenon as: a. temporal summation b. spatial summation c. synaptic summation d. saltatory summation

a. temporal summation

Although slower than an action potential, synaptic transmission is still relatively fast because: a. the synaptic cleft is very narrow. b. sodium ions are transported quickly. c. neurotransmitters diffuse faster than electricity. d. EPSPs travel faster than IPSPs.

a. the synaptic cleft is very narrow.

Temporal summation is to ____ as spatial summation is to ____. a. time, location b. EPSP, IPSP c. location, time d. depolarization, hyperpolarization

a. time, location

_____ are glial cells that have nutritive and supportive functions

astrocytes

A temporary hyperpolarization is known as an: a. EPSP. b. IPSP. c. ISPS. d. EPIP.

b. IPSP.

The research that firmly established synaptic communication as chemical was: a. Elliot's adrenaline mimicking sympathetic activation. b. Loewi's transfer of fluid from stimulated frog hearts. c. Sherrington's study of reflexes. d. Eccles's measurement of IPSPs.

b. Loewi's transfer of fluid from stimulated frog hearts.

Which of the following statements regarding reflexes would Charles Sherrington most likely agree with? a. The overall speed of conduction through a reflex arc is faster than conduction along an axon. b. Repeated stimuli occurring within a brief time can have a cumulative effect. c. Each neuron physically merges with the next one. d. Excitatory synapses are more important than inhibitory synapses.

b. Repeated stimuli occurring within a brief time can have a cumulative effect.

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

b. Spatial summation depends on contributions from more than one sensory neuron.

What do dopamine, norepinephrine, and epinephrine share in common? a. They all affect the same receptors. b. They are all synthesized from the same amino acids. c. They are all released by the same neurons. d. They all are gases.

b. They are all synthesized from the same amino acids.

Which of the following is TRUE about EPSPs? a. It takes two to produce an action potential. b. They decay over time and space. c. They can be either excitatory or inhibitory. d. They occur because potassium gates open.

b. They decay over time and space.

Which one of Sherrington's inferences about the synapse was WRONG? a. Transmission at a synapse is slower than transmission of impulses along an axon. b. Transmission at the synapse is primarily an electrical process. c. Synapses can be either excitatory or inhibitory. d. Synapses make spatial summation and temporal summation possible.

b. Transmission at the synapse is primarily an electrical process.

If you eat a food containing tryptophan, what can you consume with it to increase its entry to the brain? a. phenylalanine b. carbohydrates c. fats d. thiamine

b. carbohydrates

Which of the following neurotransmitters is released by active neurons to dilate the blood vessels and increase blood flow? a. endorphins b. glycine c. nitric oxide d. acetylcholine

c. nitric oxide

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? a. spatial summation b. temporal summation c. saltatory conduction d. synaptic combination

c. saltatory conduction

The amino acid tryptophan is the precursor to which neurotransmitter? a. dopamine b. endorphin c. serotonin d. nitric oxide

c. serotonin

Simultaneous weak stimuli at different locations produce a greater reflexive response than one of the stimuli by itself. What is this phenomenon called? a. Sherrington's law b. temporal summation c. spatial summation d. the all-or-none law

c. spatial summation

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

c. the speed of reflexive responses

What was the first evidence reported by T. R. Elliott suggesting that synapses operate chemically? a. Adrenaline mimics the effects of the parasympathetic nervous system. b. Adrenaline decreases heart rate. c. Adrenaline produces a hormone which decreases heart rate. d. Adrenaline mimics the effects of the sympathetic nervous system.

d. Adrenaline mimics the effects of the sympathetic nervous system.

What do temporal summation and spatial summation have in common? a. Both involve the activity of only two neurons. b. Both require a response from the brain. c. Both depend on a combination of visual and auditory stimuli. d. Both enable a reflex to occur in response to weak stimuli.

d. Both enable a reflex to occur in response to weak stimuli.

____ are a category of chemicals including adenosine and several of its derivatives. a. Neuropeptides b. Acetylcholine c. Monoamines d. Purines

d. Purines

An IPSP represents: a. the location where a dendrite branches. b. a gap in a myelin sheath. c. a subthreshold depolarization. d. a temporary hyperpolarization.

d. a temporary hyperpolarization.

The catecholamines include: a. epinephrine, norepinephrine, dopamine, and serotonin. b. epinephrine, serotonin, and dopamine. c. dopamine, serotonin, and acetylcholine. d. epinephrine, norepinephrine, and dopamine.

d. epinephrine, norepinephrine, and dopamine.

An action potential causes the release of neurotransmitters by: a. blocking potassium pores in the membrane. b. opening chloride pores in the membrane. c. blocking iron pores in the membrane. d. opening calcium pores in the membrane.

d. opening calcium pores in the membrane.

Temporal summation most likely occurs with: a. infrequent, subthreshold excitation. b. rapid succession of stimuli that each exceed threshold. c. infrequent, inhibitory stimuli. d. rapid succession of subthreshold excitation.

d. rapid succession of subthreshold excitation.

The "decision" for a neuron to fire is determined by the: a. number of EPSPs only. b. spontaneous firing rate. c. number of IPSPs only. d. ratio of EPSPs to IPSPs.

d. ratio of EPSPs to IPSPs.

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

d. record depolarizations of the postsynaptic neuron.

The proper order of a reflex arc is: a. motor neuron, sensory neuron, interneuron. b. sensory neuron, motor neuron, interneuron. c. motor neuron, interneuron, sensory neuron. d. sensory neuron, interneuron, motor neuron.

d. sensory neuron, interneuron, motor neuron.

Specialized junctions between neurons are called: a. nodes of Ranvier. b. spines. c. dendrites. d. synapses.

d. synapses.

Reuptake is an alternative to which other process?

enzymatic breakdown of neurotransmitters

Depolarization is to _____ as hyper polarization is to ______.

excitation, inhibition.

Exocytosis is the process by which proteins are ______

excreted in the synaptic cleft

cerebellum

focusing and shifting attention and organizing sensory inputs

cell differentiation is the

formation of dendrites and an axon

Cells that aid and modulate neurons' activities are called _________

glial cells

Central structures of the brain include

hindbrain, midbrain, thalamus, and hypothalamus

The function of a myelin sheath is to

increase velocity of transmissions along an axon.

the hippocampus and the cingulate cortex have been implicated in

memory and attention

the glial cell that operates as the brains immune system?

microglia

phagocytosis, or the breakdown of any foreign tissue or dead brain cells, is carried out by

microglial cells

a large collection of axons coursing together outside the central nervous system is a what

nerve

If there is a depolarizing effect on a neuron, the result would be that the neuron will fire

only if it reaches the threshold.

sensory functions are localized to the _____

posterior

the cell membrane forms a ______ barrier that allows certain molecules inside of the cell and exclude others, which means it is ___________

protective; semi permeable

Allowing only certain people to cross the street, and only at certain times, is comparable to a neuron's ____ with respect to ions

selective permeability.

After a meal that was rich in the amino acid trypotophan, which neurotransmitter level would increase the most?

serotonin

Compared to ionotropic effects, metaotropic effects are

slower and long-lasting

basal ganglia

subcortical forebrain nuclei that coordinate voluntary movements of the limbs and body

correct sequences of chemical events at a synapse is

synthesis, transport, release, reuptake

primary function of the thalamus is

transmission of sensory inputs to the cortex

The circuit from sensory neuron to muscle response is called: a. a reflex arc. b. a synapse. c. flexion. d. extension.

a. a reflex arc.

the presences of microglia is a marker for

brain damage and brain inflammation

the sodium-potassium pump:

continuously exchanges three intracellular NA for two extracullar K

spatial

occurs at many different spots

the resting potential of a neuron refers to

the net negative charge on the inside of the neuron

Which of the following would produce spatial summation? a. Present two or more weak stimuli at the same time. b. Start action potentials at both ends of one axon at the same time. c. Do not allow a flexor muscle to relax before stimulating it again. d. Present a rapid sequence of weak stimuli.

a. Present two or more weak stimuli at the same time.

In addition to influencing other neurons, ____ dilates the nearby blood vessels, thereby increasing blood flow to that area of the brain. a. endorphins b. glycine c. nitric oxide d. acetylcholine

c. nitric oxide

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

d. interneurons.

Acetylcholine is synthesized in the

presynaptic terminal

________ is an electrical charge across the cell membrane in the absence of a stimulus

resting potential

Which would not most interfere with neurogensis during development?

stem cell proliferation and PROGENITOR CELL proliferation

Which of the following is TRUE about the spontaneous firing rates of neurons? a. EPSPs increase the frequency. b. EPSPs decrease the frequency. c. IPSPs increase the frequency. d. One EPSP equals the effect of two IPSPs.

a. EPSPs increase the frequency.

A new drug is discovered that affects the activity of enzymes. Which of the following stages of synaptic transmission is most likely to be affected? a. Synthesis b. Diffusion c. action potential d. Release

a. Synthesis

After one frog's heart has been stimulated, an extract of fluid from that heart can make a second frog's heart beat faster. What conclusion did Otto Loewi draw from these results? a. Transmission at synapses is a chemical event. b. The sympathetic and parasympathetic nervous systems are antagonistic. c. Transmission at heart muscle synapses is electrical. d. Hormones facilitate the actions of the nervous system.

a. Transmission at synapses is a chemical event.

A normal, healthy animal never contracts the flexor muscles and the extensor muscles of the same leg at the same time. Why not? a. When the interneuron sends excitatory messages to one, inhibitory messages go to the other. b. They are mechanically connected in a way that makes it impossible for both to contract at the same time. c. Such coordination is learned through prenatal movement. d. Both muscles are controlled by branches of the same axon.

a. When the interneuron sends excitatory messages to one, inhibitory messages go to the other.

Avoiding foods with lecithin, such as eggs and peanuts, would affect which neurotransmitter level the most? a. acetylcholine b. serotonin c. GABA d. endorphin

a. acetylcholine

The basic building blocks for the majority of neurotransmitters are: a. amino acids. b. nitric oxide. c. sugars. d. carbohydrates.

a. amino acids.

depolarized is to___________ as polarized is to __________

action potential; resting potential

Glial cells

aid and modulate the neurons activities,

which would most likely interfere with migration of neurons during development?

altering the chemical paths

motor functions are localized to the _______

anterior

What would produce a hyper polarization of a neuron?

applying a negative charge inside the neuron with a micro electrode.

After serotonin or one of the catecholamine transmitters stimulates the postsynaptic receptor, most of the transmitter molecules

are absorbed by the presynaptic cell

In a myelinated axon, where are sodium gates abundant?

at the nodes of Ranvier.

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

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

An EPSP is to ____ as an IPSP is to ____. a. hyperpolarization; depolarization b. depolarization; hyperpolarization c. spatial summation; temporal summation d. temporal summation; spatial summation

b. depolarization; hyperpolarization

The neuron excretes neurotransmitter through its membrane by a process called: a. Dale's principle. b. exocytosis. c. endocytosis. d. voltage-dependent flow.

b. exocytosis.

Increased permeability to ____ would most likely result in an IPSP. a. sodium b. potassium c. calcium d. bicarbonate

b. potassium

Increased permeability to which of the following ions would most likely result in an IPSP? a. sodium b. potassium c. calcium d. bicarbonate

b. potassium

Acetylcholine is synthesized in the: a. postsynaptic terminal. b. presynaptic terminal. c. cell body. d. dendrites.

b. presynaptic terminal.

All of the following are catecholamines EXCEPT: a. dopamine. b. serotonin. c. norepinephrine. d. epinephrine.

b. serotonin.

The correct sequence of chemical events at a synapse is: a. reuptake, release, transport, synthesis b. synthesis, transport, release, reuptake c. transport, release, reuptake, synthesis d. recycle, reuse, release, return

b. synthesis, transport, release, reuptake

What causes an EPSP? a. the deactivation of cytoplasmic enzymes b. the opening of sodium channels c. the opening of potassium channels d. inherited paranormal psychic abilities

b. the opening of sodium channels

The presynaptic terminal stores high concentrations of neurotransmitter molecules in: a. axons b. vesicles c. peptides d. dendrites

b. vesicles

What makes nitric oxide unique among neurotransmitters? a. It is released before the action potential occurs. b. It is taken back up into the presynaptic neuron. c. It is a gas. d. It is composed of amino acids.

c. It is a gas.

What is the most unusual thing about the neurotransmitter nitric oxide (NO)? a. It is found only in sensory neurons. b. It is both excitatory and inhibitory. c. It is normally a poisonous gas. d. It is also known as "laughing gas."

c. It is normally a poisonous gas.

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

c. They operate on an all-or-none principle.

Which of the following is NOT true about EPSPs? a. They decay over time. b. Their strength decreases with distance. c. They operate on an all-or-none principle. d. They are depolarizations.

c. They operate on an all-or-none principle.

When an action potential reaches the end of an axon, it evokes the release of neurotransmitters by opening ____ channels in the axon terminal. a. chloride b. bicarbonate c. calcium d. oxygen

c. calcium

Large neurotransmitters are synthesized in the: a. postsynaptic terminal. b. presynaptic terminal. c. cell body. d. dendrites.

c. cell body.

Which of the following would most likely result in an IPSP? a. potassium ions entering the cell b. sodium ions entering the cell c. chloride ions entering the cell d. chloride ions leaving the cell

c. chloride ions entering the cell

Vesicles are located: a. in postsynaptic terminals. b. in dendrites. c. in presynaptic terminals. d. outside of the neuron in the extracellular fluid.

c. in presynaptic terminals.

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: a. spatial summation. b. temporal summation. c. inhibitory messages. d. the delay in transmission at synapses.

c. inhibitory messages.

What ordinarily prevents extensor muscles from contracting at the same time as flexor muscles? a. the ligaments and tendons that bind them together b. learned patterns of coordination in the cerebral cortex c. inhibitory synapses in the spinal cord d. control of both muscles by different branches of the same axon.

c. inhibitory synapses in the spinal cord

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

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

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

c. multiple weak stimulations that occur at the same time.

Neurons

carry out the brains major functions

the breakdown of drugs by the body is referred to as

catabolization

sequence of brain development

cell birth, cell migration, cell differentiation, cell maturation

_____ and _____ produce action potentials

cell bodies and axons

Large neurotransmitters are synthesized in the

cell body

NTs are synthesized in the

cell body, axon or terminals

the _______ is composed of a bilayer of fat molecules that cover the outside of neurons.

cell membrane

A graded depolarization is known as an: a. EPIP b. IPSP c. ESPN d. EPSP

d. EPSP

Which of the following is NOT a factor in determining whether or not two EPSPs combine to reach threshold? a. size of the EPSPs b. timing between them c. threshold of the postsynaptic cell d. threshold of the presynaptic cell

d. threshold of the presynaptic cell

a new drug is discovered that affects the activity of enzymes. which of the following stages of synaptic transmission is most likely to be affected?

deactivation

a change in the resting potential from -70 mv to -65 is called

depolarization

EPSP

depolarized, helps action potential, helps impulse

Acetylcholine is deactivated through

enzymatic degradation

small, found in walls of the ventricles and they make and secrete cerebrospinal fluid

ependeymal

glial cells that produce cerebrospinal fluid

ependymal cells

differentiation

genetic development

Depolarization is to ____ as hyperpolarization is to ____. a. excitation; inhibition b. inhibition; excitation c. increasing the threshold; decreasing the threshold d. decreasing the threshold; increasing the threshold

a. excitation; inhibition

Inhibitory synapses on a neuron: a. hyperpolarize the postsynaptic cell. b. weaken the cell's polarization. c. increase the probability of an action potential. d. move the potential closer to the cell's threshold.

a. hyperpolarize the postsynaptic cell.

Like an action potential, an EPSP results from: a. sodium ions entering the cell. b. potassium ions entering the cell. c. sodium ions exiting the cell. d. potassium ions exiting the cell.

a. sodium ions entering the cell.

The tiny packets that contain neurotransmitters in the presynaptic neuron are called: a. vesicles. b. bags. c. sacs. d. terminals.

a. vesicles.

the forebrain, midbrain, and hindbrain are first visible in a human embryo after about

35 days

Enzymatic degradation

a specific enzyme changes the structure of the neurotransmitter so it is not recognized by the receptor

Charles S. Sherrington was the first to infer the properties of which of the following? a. synapses b. the refractory period c. the sodium-potassium pump d. dendrites and axons

a. synapses

star shaped, structural support for neurons that transports substances between neurones and capillaries, along with enhancing brain activity by providing fueld to activation brain regions

astrocytes

____ are specialized junctions between neurons. a. Nodes of Ranvier b. Synapses c. Dendrites d. Spines

b. Synapses

Local anesthetic drugs, such as Novocain, work by

blocking the sodium gates.

Medulla oblongata

breathing, regulates heartbeat, vomiting

On the basis of what evidence were the properties of synapses first inferred? a. the electron microscope b. single-neuron recordings c. behavioral observations d. PET scans

c. behavioral observations

Cerebrospinal fluid

clear watery fluid that fills the space between the arachnoid membrane and the pia mater

According the Chalmer, knowing why and how brian activity is associated with consciousness is the:

hard problem

________ of excess NTs in the synaptic cleft occurs by metablizing or releasing the excess NTs.

inactivation

Many dendrites contain short outgrowths called spines that

increase the surface area available for synapses.

A second-messenger can do what?

initiate the production of new proteins, alter ion flow through the membrane channels, cause a series of reactions that result in the formation of new membrane channels

a receptor can directly open a channel exerting a ________ effect or it can produce slower but longer ________ effects

ionotropic, metabotropic

What purpose does the cerebrospinal fluid serve?

it may allow certain compounds access to the brain, and it probably helps the brain exrete metabolic wastes. cushions the blow buoyancy, protection, chemical stability, clearing waste

neurons with no axons

local neurons

A receptor can indirectly open a channel exerting a ______ effect or it can produce slower but longer ______ effects

metabotropic, intracellular

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

neutrotransmitters; G-proteins

the structure that contains the chromosomes is called the

nucleus

The _______ and ________ do not have a blood-brain barrier

pineal gland and area postrema

Our brains respond to plant chemicals because

plants use chemicals similar to neurotransmitters

during resting portential the cell is ____________, while during action potential the cell is ____________

polarized; depolarized

functions of the midrain

producing orienting movements, species-specific behaviors, and the perception of pain

neuroblasts and glioblasts are formed directly from

progenitor cells

What would be the effect of a drug that inhibits the action of enzyme acetylcholinesterase?

prolonged action of acetylcholine at its synapses

which patterns of post-synpatic exception will be most likely result in an action potential?

rapid sequence of EPSPs

Temporal summation most likely occurs with

rapid succession of sub threshold excitation.

the presence of an all-or-none law suggests that neurons can only convey different messages by changing their

rate or pattern of action potentials.

The decision for a neuron to fire is determined by the

ratio of EPSPs to IPSPs

_____ have an almost limitless capacity for self-renewal

stem cells

roof of the midbrain is what

tectum, interceps with the diencephalon, processing sensory inputes

floor of the midbrain is called the

tegmentum, pain

repeated impulse, brief period of time

temporal

Pert and Snyder's discovery that opiates bind with certain receptors led to what other discovery?

the endogenous chemicals that bind with those receptors.

When stating that the neuron's membrane is polarized, you are referring to a difference in electrical potentials between

the inside and the outside of the membrane

Which two factor affect the speed of an action potential?

the presence of myelin and the diameter of the axons

Which feature of a neuron limits the number of action potentials it can produce per second

the refectory period.

blood brain barrier

the tight junctions between the cells of blood vessels in the brain that prevent the passage of most substances

Reuptake is accomplished by

transporter proteins

An extreme example of tolerance would be someone who said they needed to consumed ______ on a daily basis just to maintain

whisky, beer coke.