Organic Brain Biopsychology Chapter 3

Front 1

Myasthenia gravis

Back 1

a disease in which the immune system attacks the acetylocholine receptors at the nerve-muscle joints

Front 2

Myelinated axon

Back 2

an axon covered with a myelin sheath.

Front 3

Neuromodulator

Back 3

chemical that has properties intermediate between those of a neurotransmitter and those of a hormone.

Front 4

Neurons

Back 4

cells that receive information and transmit it to other cells by donducting electrochemical impulses.
(See: Synapses)

Front 5

Neurotransmitters

Back 5

chemicals released by neurons that affect other neurons.

Front 6

Nitric oxide

Back 6

gas released by many small neurons and used as a neuromodulator.

Front 7

Norepinephrine

Back 7

a neurotransmitter.

Front 8

Peptide

Back 8

a chain of amino acids

Front 9

Postsynaptic neuron

Back 9

a neuron on the receiving end of a synapse.

Front 10

Presynaptic neuron

Back 10

a neuron on the releasing end of a synapse

Front 11

Purines

Back 11

the category of chemicals that includes adenosine.

Front 12

Reflex

Back 12

a consistent, automatic response to a stimulus.

Front 13

Reflex arc

Back 13

circuit of neurons from the sensory neurons to muscle responses that produces a reflex.

Front 14

Reuptake

Back 14

the reabsorption of most of a neurotransmitter by the presynaptic terminal.

Front 15

Second messenger

Back 15

the chemical within a neuron that, when activated by a neurotransmitter, initiates processes that carry messages to several areas within the neuron.

Front 16

Seretonin

Back 16

a neurotransmitter.

Front 17

Spatial summation

Back 17

combination of effects of activity from two or more synapses onto a single neuron.

Front 18

Spontaneous firing rate

Back 18

a periodic production of action potentials by a neuron in the absence of synaptic input.

Front 19

Substance abuse

Back 19

a maladaptive pattern of sunstance use leading to clinically significant impairment or distress.

Front 20

Sympathetic nervous system

Back 20

the network of nerves that prepare the body's organs for vigorous activity.

Front 21

Synapses

Back 21

points of communication at the gap between two neurons or between a neuron and a muscle.

Front 22

Temporal summation

Back 22

cumulative effect as a result of repeated synaptic stimulation within a brief time.

Front 23

Transporter

Back 23

amembrane protein responsible for the reuptake of a neurotransmitter after its release.

Front 24

Vesicles

Back 24

the tiny, nearly spherical packets near the axon terminals filled with a neurotransmitter.

Front 25

Acetylcholine

Back 25

a chemical similar to an amino acid, except that the NH2 group has been replaced by an N(CH3)3 group; a neurotransmitter.

Front 26

Acetylcholinesterase

Back 26

an enzyme that breaks acetylcholine into acetate and choline.

Front 27

Adenosine

Back 27

breakdown product of AMP that forms during metabolic activity; a neuromodulator that inhibits the basal forebreain cells that promote arousal and wakefulness.

Front 28

Affinity

Back 28

tendency of a drug to bind to a particular type of receptor.

Front 29

Agonist

Back 29

drug that mimics or increases the effects of a neurotransmitter.

Front 30

Alcoholism

Back 30

the inability to quit drinking or limit intake of alcohol in spite of strong intention to do so.

Front 31

Amino acids

Back 31

acids containing an amine group

Front 32

Antagonist

Back 32

drug that blocks the effects of a neurotransmitter.

Front 33

Antagonistic muscles

Back 33

pairs of muscles that move a limb in opposite directions.

ex: extensor and flexor

Front 34

Catecholamines

Back 34

compounds such as dopamine, norepinephrine, and epinephrine that contain both catechol and an amine.

Front 35

Computerized Axial Tomography
(CT or CAT scan)

Back 35

method of visualizing a living brain by injecting a dye into the blood, then passing x-rays through the head and recording them.

Front 36

COMT
(Catechol-o-methyltransferase)

Back 36

an enzyme that converts catecholamines into synaptically inactive forms.

Front 37

Depolarization

Back 37

reduction in the level of polarization across a membrane.

Front 38

Dopamine

Back 38

a neurotransmitter

Front 39

Efficacy

Back 39

tendency of a drug to activate a particular kind of receptor.

Front 40

Epinephrine

Back 40

also known as adrenaline; a hormone; also used as a neurotransmitter

Front 41

Excitatory post synaptic potential
(EPSP)

Back 41

the graded depolarization of a neuron

Front 42

Exocytosis

Back 42

excretion of neurotransmitter through the membrane of a presynaptic terminal and into the synaptic cleft between the presynaptic and postsynaptic neurons.

Front 43

G-Protein

Back 43

protein coupled to GTP (guanosine triphosphate; energy storing molecule).

Front 44

GABA
(gamma amino butyric acid)

Back 44

the most abundant inhibitory neurotransmitter

Front 45

Glutamate

Back 45

the most abundant excitatory neurotransmitter

Front 46

Graded potential

Back 46

membrane potential that varies in magnitude; doesn't follow the all-or-none law.

Front 47

Horizontal cell

Back 47

type of cell that receives input from receptors and delivers inhibitory input to bipolar cells.

Front 48

Hormones

Back 48

chemicals secreted by glands and conveyed by the blood to other organs, which are influenced by their activity.

Front 49

Inhibitory postsynaptic potential
(IPSP)

Back 49

temporary hyperpolarization of a membrane.

Front 50

Insulin

Back 50

pancreatic hormone that facilitates the entry of glucose into the cells.

Front 51

Ionotropic effect

Back 51

synaptic effect that depends on the rapid opening of a gate in the membrane.

Front 52

MAO
(monoamine oxidase)

Back 52

enzyme that converts catecholamines and serotonin into synaptically inactive forms.

Front 53

Metabotropic effect

Back 53

the effect at a synapase that produces a relatively slow but long-lasting effect through metabolic reactions.

Front 54

Monoamine

Back 54

nonacidic neurotransmitter containing an amine group formed by a metabolic change of certain amino acids.