Physiological Psychology - Chapter 2

Front 1

Sensory neurons

Back 1

a neuron that detects changes in the external or internal enviro and sends info about these changes to the CNS

Front 2

Motor neurons

Back 2

a neuron located within the central nervous system that controls the contraction of a muscle or the secretion of a gland

Front 3

Interneurons

Back 3

neuron located entirely within the CNS

Front 4

Central nervous system (CNS)

Back 4

Brain and spinal cord

Front 5

Peripheral nervous system (PNS)

Back 5

the part of the nervous system outside the brain and spinal cord, including the nerves attached to the brain and spinal cord (most of sensory organs too)

Front 6

Cell body or soma

Back 6

cell body of the neuron, which contains nucleus

Front 7

Dendrites

Back 7

a branched, treelike structure attached to the soma of a neuron; receives info from the terminal buttons of the neurons

Front 8

Synapse

Back 8

a junction between the terminal button of an axon and the membrane of another neuron

Front 9

Axon

Back 9

the long, thin cylindrical structure that conveys info from the soma of a neuron to its terminal buttons

Front 10

Multipolar neuron

Back 10

a neuron with one axon and many dendrites attached to it

Front 11

Bipolar neuron

Back 11

a neuron with one axon attached to its soma; the axon divides, with one branch receiving sensory info and the other sending the information into the CNS

Front 12

Unipolar neuron

Back 12

a neuron with one axon attached to its some; the axon divides, with one branch receiving sensory info and the other sending the info into the CNS

Front 13

Terminal buttons

Back 13

the bud at the end of a branch of an axon; forms synapses with another neuron; sends info to that neuron

Front 14

Neurotransmitter

Back 14

a chemical released by terminal button; has an excitatory or inhibitory effect on another neuron

Front 15

Membrane

Back 15

a structure consisting of lipid molecules that defines the outer boundaries of a cell and also constitutes many of the cell organelles, such as the Golgi apparatus

Front 16

Nucleus

Back 16

a structure in the central region of the cell, containing the nucleolus and chromosomes

Front 17

Ribosome

Back 17

a cytoplasmic structure made of a protein, that serves as a site of production of proteins translate from mRNA (protein synthesis*)

Front 18

Chromosome

Back 18

a strand of DNA, with associated proteins found in the nucleus; carries genetic information

Front 19

Deoxyribonucleic acid (DNA):

Back 19

a long complex macromolecule consisting of two interconnected helical strands; along with associated proteins, strands of DNA constitute chromosomes

Front 20

Gene

Back 20

the functional unit of the chromosome, which directs synthesis of 1 or more proteins

Front 21

Messenger ribonucleic acid (mRNA):

Back 21

a macromolecule that delivers genetic info concerning the synthesis of a protein from a portion of a chromosome to a ribosome (takes copy and attached to ribosome and makes proteins)

Front 22

Enzyme

Back 22

a molecule that controls a chemical reaction, combining 2 substances or breaking a substance into 2 parts (vise versa = enzymes!) (catalysts: cause reactions, not part of them)

Front 23

Non-coding RNA: (ncRNA)

Back 23

a form of RNA that does not encode for protein but has functions of its own

Front 24

Cytoplasm

Back 24

a viscuous, semiliquid substance contained in the interior of a cell & containes organelles

Front 25

Mitochondrion

Back 25

an organelle response for extracting energy from nutrients (creates and stores ATP)

Front 26

Adenosine Triphosphate

Back 26

a molecule of prime importance to cell energy metabolism; its breakdown liberates energy

Front 27

Endoplasmic Reticulum

Back 27

storage reservoir & channel for transporting chemical through the cytoplasm

Front 28

rough endoplasmic reticulum

Back 28

contains ribosomes and is involved in production of proteins

Front 29

smooth endoplasmic reticulum

Back 29

site of synthesis of lipids and provides channels for the segregation of molecules involved in various cell processes

Front 30

Golgi apparatus

Back 30

a complex of parallel membranes in the cytoplasm that wraps the products of the secretory cell (involved in removing waste)

Front 31

Exocytosis

Back 31

complex of parallel membranes in the cytoplasm that wraps the products of the secretory cell (involved in removing waste)

Front 32

Lysosomes

Back 32

an organelle surrounded by membrane, contains enzymes that break down waste products

Front 33

Cytoskeleton

Back 33

forms of microtubules and other protein fibers, non soluble, linked to each other and forming a cohesive mass that gives a cell its shape

Front 34

Microtubules

Back 34

a long strand of bundles of protein filaments arranged around a hollow core; part of the cytoskeleton and involved in transporting substance from place to place within the cell

Front 35

Axoplasmic transport

Back 35

an active process by which substances are propelled along microtubules that run the length of the axon

Front 36

Anterograde

Back 36

in a direction along an axon from the cell body towards terminal buttons

Front 37

Retrograde

Back 37

In a direction along an axon from the terminal buttons towards the cell body

Front 38

Glia

Back 38

supporting cells of CNS

Surround neurons; protect; regulate; control what goes in; housekeepers – clean out

Front 39

Three types of glial cells

Back 39

1. Astrocyte
2. Oligodendrocytes
3. Microglia

Front 40

Astrocyte

Back 40

a glial cell that provides support for neurons of the CNS, provides nutrients & other substances and regulates chemical composition of extracellular fluid

Front 41

Phagocytosis

Back 41

The process by which cells engulf and digest other cells or debris caused by cellular degeneration

Front 42

Oligodendrocytes

Back 42

a type of glial cell in the CNS that forms myelin sheaths

Front 43

Myelin sheaths

Back 43

a sheath that surround axons and insulates them, preventing messages from spreading between adjacent axons

Front 44

Node of Ranvier

Back 44

a naked portion of myelinated axon between adjacent oligodendroglia or Schwann cells

Front 45

Microglia

Back 45

smallest of glial cells; act as phagocytes and protect the brain from invading microorganisms

Front 46

Schwann cells

Back 46

a cell of the PNS that is wrapped around a myelinated axon, providing one segments of its myelin sheath

Front 47

Blood-brain barrier

Back 47

a semipermeable barrier between the blood and the brain produced by the cells in the walls of the brains capillaries

Front 48

Area postrema

Back 48

a region of the medulla where the blood-brain barrier is weak; position can be detected and induce vomiting

Front 49

Electrodes

Back 49

a conductive medium that can be used to apply electrical stimulation or to record electrical potentials

Front 50

Microelectrode:

Back 50

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

Front 51

Membrane potential

Back 51

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

Front 52

Oscilloscope

Back 52

a lab instrument that is capable of displaying a graph of voltage as a function of time on the face of a cathode ray tube
(time: x axis; voltage: y axis)

Front 53

Resting potential

Back 53

the membrane potential of a neuron when it is not being altered by excitatory or inhibitory postsynaptic potentials (approx. -70 mv in a squid axon)

Front 54

Depolarization

Back 54

reduction (toward 0) of the membrane potential of a cell from its normal resting potential

Front 55

Hyperpolarized

Back 55

an increase in the membrane potential of a cell, relative to the normal resting potential

Front 56

Action potential

Back 56

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

Front 57

Threshold of excitation

Back 57

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

Front 58

Diffusion

Back 58

movement of molecules from regions of high concentration to regions of low concentration

Front 59

Electrolytes

Back 59

an aqueous solution of a material that ionizes – namely, a soluble acid, base or salt

Front 60

Ions

Back 60

charged molecule. Cations are + and anions are –

Front 61

Electrostatic pressure

Back 61

the attractive force between atomic particles charges with opposite signs or the repulsive force between atomic particles charge with same sign

Front 62

Intracellular fluid

Back 62

fluid in cell

Front 63

Extracellular fluid

Back 63

fluid outside cell

Front 64

Sodium-potassium transporters

Back 64

a protein found in the membrane of all cells that extrudes sodium ions from and transports potassium ions into the cell

Front 65

Ion channels

Back 65

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

Front 66

Voltage dependent ion channels

Back 66

an ion channel that open or closes according to the value of the membrane potential

Front 67

All or none law

Back 67

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

Front 68

Rate law

Back 68

the principle that variations in the intensity of a stimulus or other info being transmitted in an axon are represented by variations in the rate at which that axon fires

Front 69

Saltatory conduction

Back 69

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

Front 70

Postsynaptic potentials

Back 70

alterations in the membrane potential of a postsynaptic neuron, produced by liberation of neurotransmitters at the synapse

Front 71

Presynaptic membrane

Back 71

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

Front 72

Postsynaptic membrane

Back 72

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

Front 73

Synaptic cleft

Back 73

the space between the presynaptic and postsynaptic membrane

Front 74

Synaptic vesicles

Back 74

small rounded objects in the shape of spheres or ovoids

Front 75

release zone

Back 75

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

Front 76

“KISS AND RUN”

Back 76

Fusion pore closes and synaptic vesicles lets go and filled with neurotransmitter again

Front 77

Bulk endocytosis

Back 77

large pieces fold inward and then snap off and form new small buds

Front 78

Postsynaptic receptors

Back 78

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

Front 79

Neurotransmitter-dependent ion channel

Back 79

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

Front 80

Ionotropic receptor

Back 80

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

Front 81

Metabotropic receptors

Back 81

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 82

G protein

Back 82

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

Front 83

second messenger

Back 83

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

Front 84

Excitatory postsynaptic potential (EPSP

Back 84

an excitatory depolarization of the postsynaptic membrane of a synapse caused by the liberation of a neurotransmitter by the terminal button

Front 85

inhibitory postsynaptic potential (IPSP)

Back 85

an inhibitory hyperpolarization of the postsynaptic membrane of a synapse caused by the liberation of a neurotransmitter by the terminal button

Front 86

Reuptake

Back 86

the re-entry of a neurotransmitter just liberated by a terminal button back through tis membrane, thus terminating the postsynaptic potential

Front 87

Enzymatic deactivation

Back 87

the destruction of a neurotransmitter by an enzyme after its release – for example, the destruction of acetylcholine by acetylcholinesterase

Front 88

Acetylecholine

Back 88

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

Front 89

Acetylecholinesterase

Back 89

the enzyme that destroys acetylecholine soon after it is liberated by the terminal buttons, thus terminating the postsynaptic potential

Front 90

Neural integration

Back 90

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

Front 91

Autoreceptor

Back 91

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

Front 92

Presynaptic inhibition

Back 92

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

Front 93

Presynaptic facilitation:

Back 93

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

Front 94

Gap junction

Back 94

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

Front 95

Neuromodulator

Back 95

Naturally secreted substance that acts like a neurotransmitter except that its not restricted to the synaptic cleft but diffuses through the extracellular fluid

Front 96

peptides

Back 96

a chain of amino acids joined together by peptide bonds

Front 97

Hormones

Back 97

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

Front 98

Endocrine gland

Back 98

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

Front 99

Target cells

Back 99

cells that contain receptors for certain hormones

Front 100

Steroid

Back 100

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