Synapses

Question 1

A specialized gap between neurons

Answer 1

Synapse

Question 2

Automatic muscular responses to stimuli

Answer 2

Reflexes

Question 3

The circuit from sensory neuron to muscle response

Answer 3

Reflex arc

Question 4

What does the synapse do to the transmission of reflex impulses?

Answer 4

Delays neuron communication

Question 5

Phenomenon: repeated stimuli within a brief time have a cumulative effect

Answer 5

Temporal summation

Question 6

The neuron that delivers transmissions

Answer 6

Presynaptic neuron

Question 7

The neuron that receives transmissions

Answer 7

Postsynaptic neuron

Question 8

Rapid succession of weak stimuli is enough to produce _________

Answer 8

An action potential

Question 9

Unlike action potentials, which are always depolarizations, graded potentials ________

Answer 9

May either be depolarizations or hyperpolarizations

Question 10

Depolarization that results from a flow of sodium ions into the postsynaptic neuron

Answer 10

Excitatory postsynaptic period (EPSP)

Question 11

Phenomenon: Synaptic inputs from separate locations combine their effects on a neuron

Answer 11

Spatial summation

Question 12

Temporal summation and spatial summation ordinarily occur _______

Answer 12

Together/at the same time

Question 13

Temporary hyperpolarization that results from potassium ions leaving the membrane or for chloride ions to leave the cell

Answer 13

Inhibitory postsynaptic potential (IPSP)

Question 14

What ion gates open during an EPSP?

Answer 14

Sodium gate

Question 15

What ion gates open during an IPSP?

Answer 15

Potassium or chloride gates

Question 16

Can an inhibitory message flow along an axon?

Answer 16

No. Only action potentials propagate along an axon. Inhibitory messages—IPSPs—decay over time and distance

Question 17

The summation of graded potentials from stimuli at different times

Answer 17

Temporal summation

Question 18

The summation of potentials from different locations

Answer 18

Spatial summation

Question 19

The balance between __________ increases are decreases the neuron’s frequency of action potentials

Answer 19

EPSPs and IPSPs

Question 20

Set of nerves that accelerates the heartbeat, relaxes the stomach muscles, dilates the pupils of the eyes, and regulates other organs

Answer 20

Sympathetic nervous system

Question 21

First sequence of chemical events at the synapse

Answer 21

Synthesize neurotransmitters

Question 22

Second sequence of chemical events at the synapse

Answer 22

Action potential causes calcium to enter, releasing neurotransmitters

Question 23

Third sequence of chemical events at the synapse

Answer 23

Neurotransmitter binds to receptor

Question 24

Fourth sequence of chemical events at the synapse

Answer 24

Separation of neurotransmitters from the receptor

Question 25

Fifth sequence of chemical events at the synapse

Answer 25

Reuptake of neurotransmitter by transporter protein for recycling or diffusion

Question 26

Sixth sequence of chemical events at the synapse

Answer 26

Postsynaptic cells send reverse messages to control further release of neurotransmitters

Question 27

Chemicals that affect another neuron

Answer 27

Neurotransmitters

Question 28

Neurotransmitter that dilates nearby blood vessels, increasing blood flow to certain brain areas but are also poisonous large qualities

Answer 28

Nitric oxide

Question 29

Neurons synthesize nearly all neurotransmitters from _______

Answer 29

Amino acids

Question 30

Amino acid synthesized from choline which is abundant in milk, egg, and peanuts

Answer 30

Acetylcholine

Question 31

Amino acids that are the precursors of dopamine, norepinephrine, and epinephrine

Answer 31

Phenylalanine and tyrosine

Question 32

Amino acid that is the precursor to serotonin and can cross the blood-brain barrier by a special transport system. Found in foods like soy.

Answer 32

Tryptophan

Question 33

What are three catecholamine neurotransmitters?

Answer 33

Epinephrine, norepinephrine, and dopamine

Question 34

Tiny, nearly spherical packets that store high concentrations of neurotransmitter molecules

Answer 34

Vesicles

Question 35

Enzyme that breaks down serotonin, dopamine, or norepinephrine into inactive chemicals to prevent harmful levels of accumulation

Answer 35

Monoamine oxidase (MAO)

Question 36

What happens by blocking MAO?

Answer 36

Increases serotonin, dopamine, and norepinephrine levels in the brain