Physiology Of Behavior Neil Carlson Pg 41-64

Front 1

Electrode

Back 1

A conducive medium that can be used to apply electrical stimulation or record electrical potentials.

Front 2

Mircoelectrode

Back 2

A very fine electrode, generally used to record activity of individual neurons.

Front 3

Membrane Potential

Back 3

The electrical charge across a cell membrane; the difference in electrical potential inside and outside the cell.

Front 4

Oscilloscope

Back 4

A laboratory instrument that is capable of displaying a graph of voltage as a function of time on the face of a cathode ray tube.

Front 5

Resting Potential

Back 5

The membrane potential of a neuron when it is not being altered by excitatory or inhibitory postsynaptic potentials; approximately -70 mV in the giant squid axon.

Front 6

Depolarization

Back 6

Reduction (toward zero) of the membrane potential of a cell from its normal resting potential.

Front 7

Hyperpolarization

Back 7

An increase in he membrane potential of a cell, relative to the normal resting potential.

Front 8

Action Potential

Back 8

The brief electrical impulse that provides the basis for conduction of information along the axon.

Front 9

Threshold of Excitation

Back 9

The value of the membrane potential that must be reached to produce an action potential.

Front 10

Diffusion

Back 10

Movement of molecules from regions of high concentration to regions of low concentration.

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Electrolyte

Back 11

A aqueous solution of a material that ionizes namely, a soluble acid, base, or salt.

Front 12

ion

Back 12

A charged molecule. Cations are positively charged, and anions are negatively charged.

Front 13

Electrostatic Pressure

Back 13

The attractive force between atomic particles charged with opposite signs or the repulsive force between atomic particles charged with the same sign.

Front 14

Intracellular Fluid

Back 14

The fluid contained within the cells.

Front 15

Extracellular Fluid

Back 15

The fluids located outside of the cells.

Front 16

Sodium-Potassioum Transporter

Back 16

A protein found in the membrane of all cells that extrudes sodium ion from and transport potassium ion into the cell.

Front 17

ion channel

Back 17

A specialized protein molecule that permits specific ions to enter or leave cells

Front 18

Voltage-dependent ion channel

Back 18

An ion channel that opens or closes according to the value of the membrane potential.

Front 19

All or None Law

Back 19

The principal that once an action potential is triggered in an axon, it is propagated, without decrement to the end of the fiber.

Front 20

Rate Law

Back 20

The principal that variations in the intensity of stimulus or other information being transmitted in an axon are represented by variations in the rate at which that axon fires.

Front 21

Saltatory Conduction

Back 21

Conductions of action potentials by myelinated axons. The action potential appears to jump from one node of Ranvier to the next.

Front 22

Postsynaptic Potentials

Back 22

Alterations in the membrane potentials of a postsynaptic neuron, produced by liberation of neurotransmitter at the synapse.

Front 23

Binding Site

Back 23

The Location on a receptor protein to which a ligand binds.

Front 24

Ligand

Back 24

A chemical that binds with the binding site of a receptor.

Front 25

Dendritic Spine

Back 25

A small bud on the surface of a dendrite with which a terminal button of another neuron forms a synapse.

Front 26

Presynaptic Membrane

Back 26

The membrane of a terminal button that lies adjacent to the postsynaptic membrane and through which the neurotransmitter is released.

Front 27

Postsynaptic Membrane

Back 27

The cell membrane opposite the terminal button in the synapse; the membrane of the cell that receives the message.

Front 28

Synaptic Cleft

Back 28

The space between the presynaptic membrane and the postsynaptic membrane.

Front 29

Synaptic Vesicle

Back 29

A small, hollow, beadlike structure found in the terminal buttons, contains molecules of a neurotransmitter.

Front 30

Release Zone

Back 30

A region of the interior of the presynaptic membrane of a synapse to which synaptic vesicles attach and release their neurotransmitter into the synaptic cleft.

Front 31

Postsynaptic receptor

Back 31

A receptor molecule in the postsynaptic membrane of a synapse that contains a binding site for a neurotransmitter.

Front 32

Neurotransmitter-dependent ion channel

Back 32

An ion channel that opens when a molecule of a neurotransmitter binds with a postsynaptic receptor.

Front 33

Iontropic Receptor

Back 33

A receptor that contains a binding site for a neurotransmitter and an ion channel that opens when a molecule of the neurotransmitter attaches to the binding site.

Front 34

Metabotropic Receptor

Back 34

A receptor that contains a binding site for a neurotransmitter; activates an enzyme that begins a series of events that opens an ion channel elsewhere in the membrane of the cell when a molecule of the neurotransmitter attaches to the binding site.

Front 35

G Protein

Back 35

A protein coupled to a metabotropic receptor; conveys messages to other molecules when a ligand binds with and activates the receptor.

Front 36

Second Messenger

Back 36

A chemical produced when a G protein activates an enzyme; carries a signal that results in the opening of the ion channel or causes other events to occur in the cell.

Front 37

Excitatory Postsynaptic Potential (EPSP)

Back 37

An excitatory depolarization (from influx of + ions) of the postsynaptic membrane of a synapse caused by the liberation of a neurotransmitter by the terminal button.

Front 38

Inhibitory Postsynaptic Potential (IPSP)

Back 38

An inhibitory hyperpolarization (from influx of - ions or efflux of + ion) of the postsynaptic membrane of a synapse caused by the liberation of a neurotransmitter by the terminal button.

Front 39

Reuptake

Back 39

The reentry of a neurotransmitter just liberated by a terminal button back through its membrane, thus terminating the postsynaptic potential.

Front 40

Enzymatic Deactivation

Back 40

The destruction of a neurotransmitter by an enzyme after its release.

Front 41

Acetylcholine (ACh)

Back 41

A neurotransmitter found in the brain, spinal cord, and parts of the peripheral nervous system; responsible for muscular contraction.

Front 42

Acetylcholinesterase (AChE)

Back 42

The enzyme that destroys acetylcholine soon after its liberated by the terminal buttons, thus terminating the postsynaptic potential.

Front 43

Neural Integration

Back 43

The process by which inhibitory and excitatory postsynaptic potentials summate and control the rate of firing a neuron.

Front 44

Autoreceptor

Back 44

A receptor molecule located on a neuron that responds to the neurotransmitter released by that neuron.

Front 45

Presynaptic Inhibition

Back 45

The action of a presynaptic terminal button in an axoaxonic synapse; reduces the amount of neurotransmitter released by the postsynaptic terminal button.

Front 46

Presynaptic Inhibition

Back 46

The action of a presynaptic terminal button in an axoaxonic synapse; increases the amount of neurotransmitter released by the postsynaptic terminal button.

Front 47

Gap Junction

Back 47

A special junction between cells that permits direct communication by means of electrical coupling.

Front 48

Neuromodulator

Back 48

A naturally secreted substance that acts like a neurotransmitter except that it is not restricted to the synaptic cleft but diffuses through the extracellular field.

Front 49

Peptide

Back 49

A chain of amino acids joined together by peptide bonds. Most neuromodulators, and some hormones, consist of peptide molecules.

Front 50

Hormone

Back 50

A chemical substance that is released by an endocrine gland that has effects on target cells in other organs.

Front 51

Endocrine Glands

Back 51

A gland that liberates its secretions into the extracellular fluid around capillaries and hence into the bloodstream.

Front 52

Target Cell

Back 52

The type of cell that is directly affected by a hormone or other chemical signal.

Front 53

Steroid

Back 53

A chemical of low molecular weight, derived from cholesterol. Steroid hormones affect their target cells by attaching to receptors found within the nucleus.