chapter 2 Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

central nervous system

A

the brain and spinal cord

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

peripheral nervous system

A

the part of the nervous system outside of the brain and spinal cord, including the nerves attached to the brain and spinal cord

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

nerves

A

bundles of individual neurons contained within a protective membrane that relay sensory to the CNS from the body and relay motor information from the CNS to the rest of the body.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

sensory neuron

A

a neuron that detects changes in the external or internal environment and sends information about these changes to the central nervous system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

motor neuron

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

interneuron

A

a neuron located entirely within the central nervous system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

soma

A

the cell body of a neuron which contains the nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

dendrite

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

synapse

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

axon

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

axoplasmic transport

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

anterograde

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

retrograde

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

myelin sheath

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

terminal buttons

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

neurotransmitter

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

membrane

A

a structure consisting principally of lipid molecules that defines the outer boundaries of a cell and also constitutes many of the cell organelles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

cytoskeleton

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

microtubule

A

a long strand of bundles of protein filaments arranged around a hollow core; part of the cytoskeleton and involved in transporting substances from place to place within the cell (tracks for the axoplasmic transport)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

cytoplasm

A

the viscous, semiliquid substance contained in the interior of a cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

nucleus

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

chromosome

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

deoxyribonucleic acid (DNA)

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

gene

A

the functional unit of the chromosome which directs synthesis of one or more proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

enzyme

A

a molecule that controls a chemical reaction, combining two substances or breaking a substance into two parts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

mitochondria

A

organelles that are responsible for extracting energy from nutrients

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

adenosine triphosphate (ATP)

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

gila

A

the supporting cells of the central nervous system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

astrocyte

A

a gila cell that provides support for neurons of the central nervous system, provides nutrients and other substances, and regulates the chemical composition of the extracellular fluid.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

phagocytosis

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

oligodendrocytes

A

a type of gilial cell in the central nervous system that forms myelin sheath

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

node of ranvier

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

microgila

A

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

34
Q

schwann cells

A

a cell in the peripheral nervous system that is wrapped around a myelinated axon, providing one segment of its myelin sheath

35
Q

blood-brain barrier

A

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

36
Q

area postrema

A

a region of the medulla where the blood-brain barrier is weak; poison’s can be detected there and can initiate vomiting

37
Q

membrane potential

A

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

38
Q

resting potential

A

the membrane potential of a neuron when it is not being altered by excitatory or inhibitory postsynaptic potentials; approximately -70mV in many neurons

39
Q

hyperpolarization

A

an increase in the membrane potential of a cell, relative to the normal resting potential (its more negative than its outside)

40
Q

depolarization

A

reduction toward zero of the membrane potential of a cell from its normal resting potential ( its more positive than its outside)

41
Q

threshold of excitation

A

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

42
Q

action potential

A

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

43
Q

diffusion

A

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

44
Q

ion

A

a charged molecule. cations are positively charged and anions are negatively charged

45
Q

electrostatic pressure

A

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

46
Q

intracellular fluid

A

the fluid contained within cells

47
Q

extracellular fluid

A

body fluids located outside of cells

48
Q

sodium-potassium transporters

A

a protein found in the membrane of all cells that extrudes sodium ions from and transports potassium ions into the cell. Pump three sodium ions out for every two potassium ions in.

49
Q

ion channel

A

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

50
Q

voltage-dependent ion channel

A

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

51
Q

all-or-none law

A

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

52
Q

rate law

A

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

53
Q

saltatory conduction

A

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

54
Q

postsynaptic potential

A

brief depolarizations or hyperpolarization that increase or decrease the rate of action potentials in the axon of the postsynaptic neuron

55
Q

binding site

A

the location on a receptor protein to which a ligand binds

56
Q

ligand

A

a chemical that binds with the binding site of a receptor

57
Q

dendritic spine

A

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

58
Q

presynaptic membrane

A

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

59
Q

postsynaptic membrane

A

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

60
Q

synaptic vesicle

A

a small, hollow, beadlike structure found in terminal buttons; contains molecules of a neurotransmitter

61
Q

postsynaptic receptor

A

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

62
Q

neurotransmitter-dependent ion channel

A

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

63
Q

ionotropic receptor

A

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

64
Q

metabotropic receptor

A

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

65
Q

G protein

A

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

66
Q

second messenger

A

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

67
Q

excitatory postsynaptic potential

A

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

68
Q

inhibitory postsynaptic potential

A

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

69
Q

reuptake

A

the reentry of a neurotransmitter released from a terminal button back through its membrane. this process terminates the postsynaptic potential

70
Q

enzymatic deactivation

A

the destruction of a neurotransmitter by an enzyme after its release

71
Q

acetylcholinesterase

A

the enzyme that destroys acetylcholine soon after it is released from the terminal buttons. this action terminates the postsynaptic potential

72
Q

acetylcholine

A

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

73
Q

neural integration

A

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

74
Q

autoreceptor

A

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

75
Q

presynaptic inhibition

A

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

76
Q

presynaptic facilitation

A

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

77
Q

neuromodulator

A

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

78
Q

peptide

A

a chain of amino acids joined together by peptide bonds. most neuromodulators and some hormones consist of peptide molecules

79
Q

hormone

A

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

80
Q

endocrine gland

A

a gland that releases chemical messengers into the extracellular fluid around capillaries and hence into the bloodstrem

81
Q

target cell

A

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