Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Cell And Molec > exam 4 > Flashcards

exam 4 Flashcards

1
Q

Which of the following is a short-range signaling mechanism that enables cells to signal to other cells via secreted local mediators?

A

endocrine

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

Which of the following binding domains enables proteins to bind to phosphoinositides?

A

PH

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

The secondary messenger, cAMP activates which enzyme?

A

PKA

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

Protein that binds to a GTP- binding protein and activates it by stimulating release of tightly bound GDP, thereby allowing it to bind GTP

A

Guanine nucleotide exchange factor (GEF)

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

General term for a protein that binds a specific extracdllular molecule (ligand) and initiates a response in the cell

A

receptor

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

Alteration of sensitivity following repeated stimulation, reducing a cells response to that level of stimulus

A

adaptation or desensitization

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

Compact protein module that binds to a particular structural motif in another protein (or lipid) molecule with which the signaling protein interacts

A

interaction domain

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

Short-range cell-cell communication via secreted local mediators that act on adjacent cells

A

paracrine signaling

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

A signal relay chain involving multiple protein kinases, each of which is activated by phosphorylation and then phosphorylates the next protein kinase in the sequence

A

kinase cascade

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

Small molecule that is formed in the cytosol, or released into it, in response to an extracellular signal and that helps to relay the signal to the interior of the cell

A

second messenger

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

Specialized animal cell that secretes a hormone into the blood

A

endocrine cell

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

Molecule from outside the cell that communicates the behavior or actions of other cells in the environment and elicits an appropriate response

A

extracellular signal molecule

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

Enzyme that transfers the terminal phosphate group of ATP to a specific amino acid of a target protein

A

protein kinase

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

Small signal molecule secreted by the presynaptic nerve cell at a chemical synapse to relay the signal to the postsynaptic cell

A

neurotransmitter

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

Protein that binds to a GTP-binding protein and inactivates it by stimulating its GTPase activity so that its bound GTP is hydrolyzed to GDP

A

GTP-ase activating protein

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

Protein that organizes groups of interacting intracellular signaling proteins into signaling complexes

A

scaffold protein

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

Cell-cell communication in which the signal molecule remains bound to the signaling cell and only influences cells that physically touch it

A

contact-dependent signaling

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

G protein that activates adenylyl cyclase and thereby increases cyclic AMP concentration

A

stimulatory G protein

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

Protein composed of three subunits, one of which is activated by the binding of GTP

A

trimeric GTP-binding protein

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

Ubiquitous calcium-binding protein whose interactions with other proteins are governed by changes in intracellular Ca2+ concentration

A

Calmodulin

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

Enzyme that hydrolyzes cyclic AMP to adenosine 5’-monophosphate (5’-AMP)

A

cyclic AMP phosphodiesterase

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

Cell-surface receptor that associates with an intracellular G protein upon activation by an extracellular ligand

A

G-protein-coupled receptor

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

Enzyme that participates in desensitization of GPCRs by phosphorylating them after they have been activated by ligand binding

A

GPCR kinase

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

Ca2+ release channel in the ER membrane that is activated by Ca2+ binding in the absence of IP3

A

ryanodine receptor

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

Enzyme bound to the cytoplasmic surface of the plasma membrane that converts membrane PI(4,5)P2 to diacylglycerol and IP3

A

phospholipase C-B (PLCB)

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

Protein that is an a-subunit-specific GTPase-activating protein (GAP)

A

regulator of G protein signaling (RGS)

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

Second messenger that is released from a phospholipid in the plasma membrane and diffuses to the ER, where it opens Ca2+ release channels

A

inositol 1,4,5-triphosphate (IP3)

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

Enzyme that phosphorylates target proteins in response to a rise in intracellular cyclic AMP

A

cyclic AMP-dependent protein kinase (PKA)

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

A Ca2+ dependent protein kinase that is activated by diacylglycerol

A

protein kinase C (PKC)

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

Light sensitive GPCR in rod photoreceptor cells of the retina

A

rhodopsin

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

Protein kinase whose activity is regulated by the binding of Ca2+ activated calmodulin, and which indirectly mediates the effects of Ca2+ by phosphorylation of other proteins

A

Ca2+/calmodulin-dependent kinase (CaM-kinase)

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

Protein that binds to the cyclic AMP response elements found in the regulatory region of many genes activated by cyclic AMP

A

CRE-binding (CREB) protein

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

The largest class of cell-surface-bound extracellular signal proteins

A

Ephrins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Large family of structurally related, secreted, dimeric proteins that act as hormones and local mediators to control a wide range of biological function in all animals

A

transforming growth factor-B superfamily (TGFB)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Cell-surface receptor that when activated by ligand binding adds phosphates from ATP to tyrosine side chains in its own cytoplasmic domain

A

receptor tyrosine kinase (RTK)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

The founding member of a superfamily of monomeric GTPases that help to relay signals from cell-surface receptors to the nucleus

A

Ras

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

A group of monomeric GTPases that regulate both the actin and microtubule cytoskeletons

A

Rho family

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Cytoplasmic tyrosine kinase present at cell-matrix junctions in association with the cytoplasmic tails of integrins

A

focal adhesion kinase (FAK)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

A kinase that is involved in intracellular signaling pathways activated by cell-surface receptors and that phosphorylates inositol phospholipids at the 3 position of the inositol ring

A

phosphoinositide 3-kinase (PI 3-kinase)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Cell-surface receptor that activates a tyrosine kinase that is noncovalently bound to the receptor

A

tyrosine-kinase-associated receptor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

A three-component signaling module used in various signaling pathways in eukaryotic cells

A

MAP kinase module

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

One of several intracellular signaling pathways that leads from cell-surface receptors to the nucleus, it is distinguished by providing one of the more direct routes

A

JAK-STAT signaling pathway

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Protein domain found in intracellular signaling proteins by which they bind to inositol phospholipids phosphorylated by PI 3-kinase

A

Pleckstrin homology (PH) domain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

A protein domain that is homologous to a region in Src, is present in many proteins, and binds to a short amino acid sequence containing a phosphotyrosine

A

SH2 domain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

A crucial signaling protein in the PI-3-kinase-Akt signaling pathway, so named because it is the target of rapamycin

A

TOR or mTOR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Receptor protein involved in what may be the most widely used signaling pathway in animal development; its ligands are cell-surface proteins such as Delta

A

Notch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

A family of secreted signal molecules that act as local mediators and morphogens during development; they were initially discovered as the products of the Wingless gene in flies and the Int1 gene in mice

A

Wnt proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

A signaling pathway activated by Wnt binding to both the Frizzled receptor and the LRP co-receptor

A

Wnt/B-catenin pathway

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

A group of secreted signal molecules that act as local mediators and morphogens during development and whose effects are mediated through the cell-surface receptor Patched and its binding partner Smoothened

A

Hedgehog proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

A target of Hedgehog signaling, this gene regulatory molecule is a full length gene activator in the presence of Hedgehog and a partially proteolyzed gene repressor in its absence

A

Cubitus interruptus (Ci)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

Latent gene regulatory proteins that are present in most cells in both animals and plants and are central to many stress, inflammatory, and innate immune responses

A

NFKB proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

Hydrophobic signaling molecule with a characteristic four-ringed structure derived from cholesterol

A

steroid hormone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

A linear chain of protein subunits joined end to end, which associates laterally with other such chains to form cytoskeletal components

A

protofilament

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

System of protein filaments in the cytoplasm of a eukaryotic cell that gives the cell its shape and the capacity for directed movement

A

cytoskeleton

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

The process by which a polymeric protein filament is maintained at constant length by addition of protein subunits at one end and loss of subunits at the other

A

treadmilling

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

Specialized layer of cytoplasm on the inner face of the plasma membrane, rich in actin filaments

A

cell cortex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

Protein assembly that nucleates actin filament growth from the minus end, allowing rapid growth at the plus end and forming a treelike web of filaments

A

Arp2/3 complex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

The motor protein in muscle that generates the force for muscle contraction

A

myosin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

Long, highly organized bundle of actin, myosin, and other proteins in the cytoplasm of muscle cells that contracts by a sliding-filament mechanism

A

myofibril

60
Q

The property of sudden conversion feom growth to shrinkage, and vice versa, in a protein filament such as a microtubule or an actin filament

A

dynamic instability

61
Q

Centrally located organelle of animal cells that is the primary microtubule-organizing center and acts as the spindle pole during mitosis

A

centrosome

62
Q

Protein assembly containing a special form of tubulin, along with other proteins, that is an efficient nucleator of microtubule growth

A

y-Tubulin ring complex (y-TuRC)

63
Q

Short cylindrical array of microtubules, a pair of which are embedded in the major microtubule-organizing center of an animal cell

A

centriole

64
Q

A member of the family of motor proteins that move along microtubules by walking toward the minus end

A

dynein

65
Q

A motor protein that moves along microtubules by walking toward the plus end

A

kinesin

66
Q

Bundle of mixrotubules and associated proteins that forms the core of a cilium or flagellum in a eukaryotic cell and is responsible for their movements

A

axoneme

67
Q

Long, hairlike protrusion from the surface of a eukaryotic cell whose endulations drive the cell through a liquid medium

A

flagellum

68
Q

A group of closely related monomeric GTPases that includes Cdc42, Rac, and Rho

A

Rho family protein

69
Q

Flattened, two-dimensional protrusion of membrane, supported by a meshwork of actin filaments, that is extended from the leading edge of crawling epithelial cells, fibroblasts, and some neurons

A

lamellipodium

70
Q

Essentially a one-dimensional structure that protrudes from a cell and contains a core of long, bundled actin filaments

A

filopodium

71
Q

A distinct form of membrane protrusion that is often observed when cells are cultured on a pliable extracellular matrix substrate

A

blebbing

72
Q

The long period of the cell cycle between one mitosis and the next

A

interphase

73
Q

The orderly sequence of events by which a cell duplicates its contents and divides into two

A

cell cycle

74
Q

The checkpoint in the cell cycle that governs the cell’s commitment to enter S phase

A

Start or restriction point

75
Q

The phase of the eukaryotic cell cycle between the end of cytokinesis and the start of DNA synthesis

A

G1 phase

76
Q

A member of the family of protein kinases that have to be complexed with a cyclin protein in order to act

A

Cyclin-dependent kinase(Cdk)

77
Q

The ubiquitin ligase that promotes the destruction of a specific set of proteins, thereby promoting the separation of sister chromatids and the completion of M phase

A

anaphase promoting complex or cyclosome (APC/C)

78
Q

The cyclin-Cdk complex responsible for stimulating entry into mitosis at the G2/M checkpoint

A

M-Cdk

79
Q

One of a family of proteins that rise and fall in concentration in step with the eukaryotic cell cycle, thereby regulating the activity of the crucial protein kinases that control progression through the cell cycle

A

cyclin

80
Q

The final major checkpoint in the cell cycle, where the control system stimulates sister-chromatid separation, leading to the completion of mitosis and cytokinesis

A

metaphase-to-anaphase transition

81
Q

A timing mechanism that triggers events of the cell cycle in a set sequence, using feedback from the processes it controls ro ensure that one stage is complete before the next one begins

A

cell-cycle control system

82
Q

General term for one of the several protein assemblies that form periodically during the cell cycle as the level of cyclin increases, and partially activate the cyclin-dependent kinase component

A

cyclin-Cdk complex

83
Q

Complex of proteins that holds sister chromatids together along their length until they separate at mitosis

A

cohesin

84
Q

Large protein complex that is bound throughout the cell cycle at origins of replication in eukaryotic chromosomes

A

origin replication complex (ORC)

85
Q

Protein that binds to and inhibits ankey component of the prereplicative complex

A

geminin

86
Q

Movement of tubulin subunits toward the spindle poles as a result of addition of new subunits at the plus ends of microtubules and their disassembly at minus ends

A

microtubule flux

87
Q

Stage of mitosis in which the spindle poles move apart

A

anaphase B

88
Q

Mechanism ensuring that cells do not enter anaphase until all chromosomes are correctly bi-oriented on the mitotic spindle

A

spindle assembly checkpoint

89
Q

Centrally located organelle of animal cells that after duplication organizes each spindle pole suring mitosis

A

centrosome

90
Q

Imaginary plane midway between the spindle poles in which chromosomes are positioned at metaphase

A

metaphase plate

91
Q

Microtubules that overlap in the spindle midzone and interact via their plus ends, generating an antiparallel array

A

interpolar microtubules

92
Q

Final stage of mitosis in which the two sets of separated chromosomes decondense and become enclosed by nuclear envelopes

A

telophase

93
Q

Complex of proteins that uses the energy of ATP hydrolysis to promote the compaction and resolution of sister chromatids

A

condensin

94
Q

Protease whose activation at the end of metaphase results in the cleavage of cohesin and the separation of sister chromatids

A

separase

95
Q

Microtubule that radiates outward from the spindle pole and contacts the cell cortex, helping to position the spindle in the cell

A

astral microtubule

96
Q

Cytoplasm containing many nuclei enclosed by a single plasma membrane

A

syncytium

97
Q

Structure formed at the end of cleavage that can persist for some time as a tether between the two daughter cells

A

midbody

98
Q

Division of the cytoplasm of a plant or animal cell into two

A

cytokinesis

99
Q

Structure made of microtubules and actin filaments that forms in the prospective plane of division of a plant cell and guides formation of the cell plate

A

phragmoblast

100
Q

Circular band containing actin and myosin that forms under the surface of animal cells undergoing cell division and contracts to pinch the two daughter cells apart

A

contractile ring

101
Q

Protease that has a cysteine at its active site and cleaves its target proteins at specific aspartic acids

A

caspase

102
Q

Wheel-like assembly composed of seven copies of the Apaf1/cytochrome c complex

A

apoptosome

103
Q

Form of cell death that leads fo fragmentation of the DNA, shrinkage of the cytoplasm, membrane changes, and cell death, without lysis or damage to neighboring cells

A

apoptosis

104
Q

An assembly of several proteins, including initiator caspases, on the cytosolic portion of the Fas death receptor

A

Death-inducing signaling complex (DISC)

105
Q

Apoptotic program triggered by the binding of an extracellular signal protein

A

extrinsic pathway

106
Q

Extracellular signal molecule that inhibits apoptosis

A

survival factor

107
Q

Apoptotic program that depends on the release into the cytosol of proteins from the mitochondrial intermembrane space

A

intrinsic pathway

108
Q

Cell-surface molecule that triggers apoptosis when bound by an extracellular signal protein

A

death receptor

109
Q

When cleaved by an initiator caspase, this protease is activated and participates in the widespread cleavage events that kill the cell

A

executioner caspase

110
Q

Ras is activated by Sos. What type of protein is Sos?

A

GEF

111
Q

MEK is downstream of Ras and activates the MAP kinase, ERK. What type of enzyme is MEK?

A

MAP kinase kinase

112
Q

What type of transcription factors do the JAKs regulate?

A

STAT

113
Q

In a growing actin filament, which end typically grows fastest?

A

plus end

114
Q

Which of these actin-binding proteins is required for the formation of Z-disks in skeletal muscle cells?

A

Alpha-actinin

115
Q

Listeria travels around within cells by constructing actin filaments using host proteins and bacterial proteins. Which of the following proteins is a bacterial protein found on the outer surface of Listeria?

A

Acta

116
Q

When are microtubules most stable?

A

when the beta subunit is binding GTP

117
Q

Microtubules radiate out from the MTOC. Which ends are furthest away from the centrioles?

A

plus ends

118
Q

What transmembrane proteins are present in focal adhesions that help cells gain traction with the extracellular matrix?

A

myosin

119
Q

Which of the following proteins is involved in the disassembly of actin filaments behind the leading edge of a migrating cell?

A

cofilin

120
Q

Which cyclins would you expect to be highly expressed during G1?

A

Cyclin D

121
Q

Which of the following regulatory proteins inhibits the activity of certain cyclin:Cdk complexes?

A

Wee1

122
Q

If cells are exposed to DNA-damaging agents they might upregulate…

A

p21

123
Q

What is the role of separase enzymes during the cell cycle?

A

cleave cohesins

124
Q

Which conditions can activate p53?

A

DNA double strand breaks caused by exposure to x- or gamma rays
DNA damage caused by UV exposure
excessive stimulation of mitogenic pathways

125
Q

Which transcription factor is inhibited by active Rb proteins?

A

E2F

126
Q

Which of the following is an anti-apoptotic member of the Bcl-2 family?

A

BclXl

127
Q

In the extrinsic pathway of apoptosis, what role does caspase-8 play?

A

it is an initiator caspase

128
Q

Name the different types of intercellular signaling

A

contact dependent
paracrine
endocrine
synaptic

129
Q

Name the types of cell surface receptors

A

ion-channel-coupled receptors
G-protein-coupled receptors
Enzyme-coupled receptors

130
Q

How are RTKs activated?

A

by signaling proteins that cause dimerization and trans-autophosphorylation

131
Q

What are the 3 main types of cytoskeletal protein filament?

A

actin, microtubules, intermediate filaments

132
Q

What is the location within the cell of actin?

A

actin is highly concentrated in the cortex just beneath the plasma membrane

133
Q

What is the location within the cell of intermediate filaments?

A

they can be beneath the inner nuclear membrane as nuclear lamina or extend across the cytoplasm

134
Q

What are microtubules attached to?

A

a microtubule organizing center (MTOC) called a centrosome

135
Q

What is nucleation?

A

it is the rate limiting step in the formation of cytoskeletal polymers

136
Q

What does troponin do?

A

controls skeletal muscle contraction by a troponin complex of T, I, and C polypeptides; tropomyosin binding, inhibitory activity, and Ca2+ binding (TIC)

137
Q

Role of tropomyosin?

A

Prevents myosin cross bridging with actin in the absence of Ca2+

138
Q

Smooth muscle contraction requires?

A

Ca2+ dependent calmodulin to activate MLCK or myosin light chain kinase

139
Q

What is kinesin and what does it do? What is dynein?

A

it is a plus end motor protein that generates force by coupling ATP hydrolysis to conformational changes
dynein is a minus end motor protein that does same thing

140
Q

What are the microtubule motor proteins and what do they do?

A

kinesins and dyneins;

they move organelles across microtubules

141
Q

Cell migration occurs how?

A

by a actin cytoskeleton that generates force

142
Q

What is dynamic instability?

A

the rapid interconversion between a growing and shrinking state of microtubules

143
Q

What is catastrophe?

A

the random loss of GTP cap that leads to rapid shrinkage in microtubule dynamic instability

144
Q

What is rescue?

A

the regain of GTP cap that leads to rapid growth in microtubule dynamic instability

145
Q

What is the function of cohesions?

A

hold sister chromatids together at the end of S phase

is a large protein complex that forms a ring around the sister chromatids

Cell And Molec (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions