test 1 ch 2

Question 1

synapse

Answer 1

gap between neurons where a specialized type of communication occurs

Question 2

charles s. sherrington

Answer 2

deduced properties of the synapse from experiments on reflexes

reflexes are slower than conduction along axon; delay at synapses

synapse is able to summate different stimuli

synapses are connected so excitation of one leads to decreased excitation or inhibition of others

Question 3

either depolarization or hyperpolarization of postsynaptic neuron

Answer 3

graded potential

Question 4

EPSP

Answer 4

excitatory postsynaptic potential that occurs when Na+ ions enter postsynaptic neuron

magnitude decreases as it moves along membrane

Question 5

repeated stimulation of one presynaptic neuron occurring within brief period of time

Answer 5

temporal summation

Question 6

presynaptic neuron

Answer 6

the neuron that delivers synaptic potential

Question 7

neuron that receives message

Answer 7

postsynaptic neuron

Question 8

several synaptic inputs originating from separate locations exerting cummulative effect on postsynaptic neuron

Answer 8

spatial summation

Question 9

temporary hyperpolarization of postsynaptic cell

Answer 9

inhibitory postsynaptic potential (IPSP)

K+ leaves cell or Cl- enters cell after stimulated

Question 10

ability to produce action potentials without synaptic input

Answer 10

spontaneous firing rate

Question 11

Otto Loewi

Answer 11

fluid from stimulated frog heart cused new heart to react as is stimulated

Question 12

exocytosis

Answer 12

action potential -> presynaptic terminal -> voltage dependent calcium channels open -> calcium influx -> neurotransmitter release into synaptic cleft

Question 13

Dale’s Principle

Answer 13

a neuron can release only one neurotransmitter

Question 14

modified (Dale’s Principle) concept

Answer 14

neuron releases same combination of neurotransmitters at all branches of its axon

Question 15

ionotropic effect of neurotransmitters

Answer 15

neurotransmitter attaches to receptor causing immediate opening of ion gate

glutamate opens sodium (Na) gates- excitatory

GABA open chloride gates- inhibitory

Question 16

metabotropic effects

Answer 16

neurotransmitter + receptor -> alters configuration of the receptor protein -> react with a G protein -> activation of second messengers

slower and longer lasting than ionotropic effects

include behaviors as taste, smell, and pain

Question 17

G protein

Answer 17

coupled to GTP (guanosine triphosphate)(energy storing molecule)

Question 18

second messengers

Answer 18

chemicals that carry a message to different areas within postsynaptic cell

Question 19

neuromodulators

Answer 19

differeent neurotransmitters utilized by metabotropic effects

release reuires repeated stimulation
released peptides trigger other neurons to release same neuropeptide
diffuse widely and affect many neurons via metabotropic receptors

Question 20

electrical synapses

Answer 20

few special purpose synapses
faster than chemical ransmissions
depolarization occurs in both cells, resulting in two nerons action as if they were one

Question 21

gap junction

Answer 21

direct contact of membrane of one neuron with membrae of another

Question 22

inactivation of neurotransmitters

Answer 22

broken down by enzymes

acetylcholine can be broken into acetate and choline by acetylcholinesterase

Question 23

myasthenia gravis

Answer 23

disorder of motor function because of deficit of Ach transmission, treated by AchE blocker

Question 24

reuptake of neurotransmitters

Answer 24

taken by transporters located on presynaptic neurons

serotonin and catecholamines are converted into inactive chemicals by enzymes

Question 25

affinity

Answer 25

how strongly drug attaches to receptor

Question 26

efficacy

Answer 26

tendency of drug to activate receptor

Question 27

nicotinic receptor

Answer 27

found in central nervous system, nerve muscle juncrion of skeletal muscles and in nucleus accumbens. stimulated by nicotine

Question 28

endorphins

Answer 28

inhibiting release of GABA which releases dopamine

Question 29

hallucinogenics

Answer 29

stimulate serotonin type 2A at inappropriate times or longer durations

Question 30

tetrahydrocannabinol

Answer 30

attaches to cannabinoid receptors throughout brain, especially cerebral cortex, cerebellum, basal ganglia, and hippocampus
located on presynaptic neuron and inhibit release of glutamate and GABA

Question 31

chemical secreted by gland or other cells that is transported to other organs by blood where alters activity

Answer 31

hormone

Question 32

responsinle for production of hormones

Answer 32

endocrine glands

Question 33

protein and peptide hormones

Answer 33

commposed of chains of amino acids and attach to membrane receptors where they activate second messenger systems

Question 34

attached to hypothalamus and consists of two distinct glands that each release different set of hormones

Answer 34

pituitary gland

Question 35

composed of glandular tissue and synthesizes secretes six releasing and inhibiting hormones that conroll anterior pituitary

Answer 35

anterior pituitary

Question 36

composed of neural tissue and can be cconsidered extension of hypothalamus, produces oxytocin and vasopressin

Answer 36

posterior pituitary

Question 37

flow through blood and stimulate anterior pituitary to release hormones, secreated from hypothalamus

Answer 37

releasing hormones