Question 1

Binding of cAMP to the _______ subunits of protein kinase A (PKA) leads to _______ of that protein kinase.

Accepted Answer

A)  catalytic; activation 
B)  catalytic; inactivation 
C)  regulatory; inactivation 
D)  regulatory; activation 
A)  catalytic; activation 
B)  catalytic; inactivation 
C)  regulatory; inactivation 
D)  regulatory; activation

Question 2

Cholera toxin inhibits the ability of the $\alpha$ subunit of Gs to split GTP. If you treated cells with cholera toxin, the resulting effect would be _______ of adenylyl cyclase.

Accepted Answer

A)  stimulation 
B)  inhibition 
C)  molecular degradation 
D)  increased synthesis 
A)  stimulation 
B)  inhibition 
C)  molecular degradation 
D)  increased synthesis

Question 3

Phosphorylation of G protein-coupled receptors by GRK

Accepted Answer

A)  turns off G protein signaling. 
B)  hypersensitizes G protein signaling. 
C)  blocks the dissociation of the G protein from the receptor. 
D)  inhibits the GTPase activity of the alpha subunit of the G protein. 
A)  turns off G protein signaling. 
B)  hypersensitizes G protein signaling. 
C)  blocks the dissociation of the G protein from the receptor. 
D)  inhibits the GTPase activity of the alpha subunit of the G protein.

Question 4

Cyclic AMP (cAMP) is synthesized from ATP by the action of

Accepted Answer

A)  phosphodiesterase. 
B)  phosphorylase kinase. 
C)  adenylyl cyclase. 
D)  protein kinase A (PK
A) . 
A)  phosphodiesterase. 
B)  phosphorylase kinase. 
C)  adenylyl cyclase. 
D)  protein kinase A (PK
A) .

Question 5

Notch is a cell-surface receptor protein that activates transcription when a piece of the Notch molecule is cleaved, enters the nucleus, and activates genes.

Accepted Answer

A) True 
 B)False

Question 6

Protein kinase A regulates glycogen metabolism by _______ glycogen synthase and _______ glycogen phosphorylase.

Accepted Answer

A)  activating; activating 
B)  inactivating; inactivating 
C)  activating; inactivating 
D)  inactivating; activating 
A)  activating; activating 
B)  inactivating; inactivating 
C)  activating; inactivating 
D)  inactivating; activating

Question 7

The signaling molecule nitric oxide (NO) functions

Accepted Answer

A)  by binding its cell surface receptor and triggering an intracellular signaling cascade. 
B)  by diffusing across the membrane and binding its intracellular receptor, which then activates transcription. 
C)  on cells located far from the cells where it was synthesized. 
D)  by diffusing across the cell membrane and changing the activities of intracellular enzymes. 
A)  by binding its cell surface receptor and triggering an intracellular signaling cascade. 
B)  by diffusing across the membrane and binding its intracellular receptor, which then activates transcription. 
C)  on cells located far from the cells where it was synthesized. 
D)  by diffusing across the cell membrane and changing the activities of intracellular enzymes.

Question 8

Why do enzymes that lie downstream of a cell surface receptor in a signal transduction pathway amplify as well as propagate the signal?

Accepted Answer

Extracellular signaling molecules typica

Question 9

Signaling molecules that activate cell surface receptors are essentially the same as those that activate intracellular receptors.

Accepted Answer

A) True 
 B)False

Question 10

Many cancers arise as a result of a breakdown in signaling pathways that control cell proliferation.

Accepted Answer

A) True 
 B)False

Question 11

Integrins are transmembrane proteins that connect

Accepted Answer

A)  the nuclear laminae to cytoplasmic kinases. 
B)  the extracellular matrix to the cytoskeleton. 
C)  focal adhesions to hemidesmosomes. 
D)  microtubules to actin filaments. 
A)  the nuclear laminae to cytoplasmic kinases. 
B)  the extracellular matrix to the cytoskeleton. 
C)  focal adhesions to hemidesmosomes. 
D)  microtubules to actin filaments.

Question 12

The action effected by protein kinase A is terminated by

Accepted Answer

A)  inactivation of the initial receptor. 
B)  inactivation of the stimulatory G protein. 
C)  degradation of cAMP. 
D)  dephosphorylation of phosphoproteins by protein phosphatase 1. 
A)  inactivation of the initial receptor. 
B)  inactivation of the stimulatory G protein. 
C)  degradation of cAMP. 
D)  dephosphorylation of phosphoproteins by protein phosphatase 1.

Question 13

SH2 domains are

Accepted Answer

A)  protein domains that bind phosphotyrosine-containing peptides. 
B)  the domains on receptor tyrosine kinases that contain the phosphorylated tyrosine. 
C)  domains that mediate the dimerization of receptor tyrosine kinases. 
D)  the domains on receptor tyrosine kinases that possess the kinase activity. 
A)  protein domains that bind phosphotyrosine-containing peptides. 
B)  the domains on receptor tyrosine kinases that contain the phosphorylated tyrosine. 
C)  domains that mediate the dimerization of receptor tyrosine kinases. 
D)  the domains on receptor tyrosine kinases that possess the kinase activity.

Question 14

What is the difference between neurotransmitters and neuropeptides?

Accepted Answer

A)  Neuropeptides are generated by neuronal cells but do not transmit signals. 
B)  Neurotransmitters are small hydrophilic molecules, and neuropeptides are small proteins. 
C)  Neurotransmitters are small protein molecules, and neuropeptides are large ones. 
D)  Some neuropeptides can act on distant cells, whereas neurotransmitters cannot. 
A)  Neuropeptides are generated by neuronal cells but do not transmit signals. 
B)  Neurotransmitters are small hydrophilic molecules, and neuropeptides are small proteins. 
C)  Neurotransmitters are small protein molecules, and neuropeptides are large ones. 
D)  Some neuropeptides can act on distant cells, whereas neurotransmitters cannot.

Question 15

Ras activation is mediated by guanine nucleotide exchange factors (GEFs) that stimulate the release of bound GDP and its exchange for GTP.

Accepted Answer

A) True 
 B)False

Question 16

Which of the following signaling pathways allows for direct cell-cell signaling by transmembrane proteins?

Accepted Answer

A)  NF-$\kappa$B 
B)  Wnt 
C)  Hedgehog 
D)  Notch 
A)  NF-$\kappa$B 
B)  Wnt 
C)  Hedgehog 
D)  Notch

Question 17

Stimulation of T lymphocytes, leading to their synthesis of a growth factor resulting in T lymphocyte proliferation, is an example of _______ signaling.

Accepted Answer

A)  autocrine 
B)  endocrine 
C)  paracrine 
D)  direct cell-to-cell 
A)  autocrine 
B)  endocrine 
C)  paracrine 
D)  direct cell-to-cell

Question 18

In glucocorticoid signaling, what would happen if Hsp90 was mutated such that it was always bound to the glucocorticoid receptor (GR)?

Accepted Answer

Normally, Hsp90 binds GR in the cytoplas

Question 19

Which signal molecule diffuses through the plasma membrane to ultimately bind nuclear receptors and influence transcription?

Accepted Answer

A)  Estrogen 
B)  Nitric oxide 
C)  Cadherins 
D)  Nerve growth factor 
A)  Estrogen 
B)  Nitric oxide 
C)  Cadherins 
D)  Nerve growth factor

Question 20

A glucocorticoid binding to its receptor stimulates

Accepted Answer

A)  phosphorylation of a transcription factor protein that activates a gene. 
B)  formation of a receptor dimer that triggers an intracellular signal pathway. 
C)  formation of a receptor dimer that binds to and activates a gene. 
D)  binding of the receptor monomer to a gene. 
A)  phosphorylation of a transcription factor protein that activates a gene. 
B)  formation of a receptor dimer that triggers an intracellular signal pathway. 
C)  formation of a receptor dimer that binds to and activates a gene. 
D)  binding of the receptor monomer to a gene.

Binding of cAMP to the _ subunits of protein kinase A (PKA) leads to _ of that protein kinase.

Cholera toxin inhibits the ability of the $\alpha$ subunit of G_s to split GTP. If you treated cells with cholera toxin, the resulting effect would be _______ of adenylyl cyclase.

Phosphorylation of G protein-coupled receptors by GRK

Cyclic AMP (cAMP) is synthesized from ATP by the action of

Notch is a cell-surface receptor protein that activates transcription when a piece of the Notch molecule is cleaved, enters the nucleus, and activates genes.

Protein kinase A regulates glycogen metabolism by _ glycogen synthase and _ glycogen phosphorylase.

The signaling molecule nitric oxide (NO) functions

Why do enzymes that lie downstream of a cell surface receptor in a signal transduction pathway amplify as well as propagate the signal?

Signaling molecules that activate cell surface receptors are essentially the same as those that activate intracellular receptors.

Many cancers arise as a result of a breakdown in signaling pathways that control cell proliferation.

Integrins are transmembrane proteins that connect

The action effected by protein kinase A is terminated by

SH2 domains are

What is the difference between neurotransmitters and neuropeptides?

Ras activation is mediated by guanine nucleotide exchange factors (GEFs) that stimulate the release of bound GDP and its exchange for GTP.

Which of the following signaling pathways allows for direct cell-cell signaling by transmembrane proteins?

Stimulation of T lymphocytes, leading to their synthesis of a growth factor resulting in T lymphocyte proliferation, is an example of _______ signaling.

In glucocorticoid signaling, what would happen if Hsp90 was mutated such that it was always bound to the glucocorticoid receptor (GR)?

Which signal molecule diffuses through the plasma membrane to ultimately bind nuclear receptors and influence transcription?

A glucocorticoid binding to its receptor stimulates

An Overview of Cells and Cell Research

Molecules and Membranes

Bioenergetics and Metabolism

Fundamentals of Molecular Biology

Genomics, Proteomics, and Systems Biology

Genes and Genomes

Replication, Maintenance, and Rearrangements of Genomic Dna

RNA Synthesis and Processing

Transcriptional Regulation and Epigenetics

Protein Synthesis, Processing, and Regulation

The Nucleus

Protein Sorting and Transport

Mitochondria, Chloroplasts, and Peroxisomes

The Cytoskeleton and Cell Movement

The Plasma Membrane

Cell Walls, the Extracellular Matrix, and Cell Interactions

The Cell Cycle

Cell Death and Cell Renewal

Cancer

Filters

Exam 17: Cell Signaling

Binding of cAMP to the _______ subunits of protein kinase A (PKA) leads to _______ of that protein kinase.

Cholera toxin inhibits the ability of the α\alphaα subunit of Gs to split GTP. If you treated cells with cholera toxin, the resulting effect would be _______ of adenylyl cyclase.

Phosphorylation of G protein-coupled receptors by GRK

Cyclic AMP (cAMP) is synthesized from ATP by the action of

Notch is a cell-surface receptor protein that activates transcription when a piece of the Notch molecule is cleaved, enters the nucleus, and activates genes.

Protein kinase A regulates glycogen metabolism by _______ glycogen synthase and _______ glycogen phosphorylase.

The signaling molecule nitric oxide (NO) functions

Why do enzymes that lie downstream of a cell surface receptor in a signal transduction pathway amplify as well as propagate the signal?

Signaling molecules that activate cell surface receptors are essentially the same as those that activate intracellular receptors.

Many cancers arise as a result of a breakdown in signaling pathways that control cell proliferation.

Integrins are transmembrane proteins that connect

The action effected by protein kinase A is terminated by

SH2 domains are

What is the difference between neurotransmitters and neuropeptides?

Ras activation is mediated by guanine nucleotide exchange factors (GEFs) that stimulate the release of bound GDP and its exchange for GTP.

Which of the following signaling pathways allows for direct cell-cell signaling by transmembrane proteins?

Stimulation of T lymphocytes, leading to their synthesis of a growth factor resulting in T lymphocyte proliferation, is an example of _______ signaling.

In glucocorticoid signaling, what would happen if Hsp90 was mutated such that it was always bound to the glucocorticoid receptor (GR)?

Which signal molecule diffuses through the plasma membrane to ultimately bind nuclear receptors and influence transcription?

A glucocorticoid binding to its receptor stimulates

An Overview of Cells and Cell Research

Molecules and Membranes

Bioenergetics and Metabolism

Fundamentals of Molecular Biology

Genomics, Proteomics, and Systems Biology

Genes and Genomes

Replication, Maintenance, and Rearrangements of Genomic Dna

RNA Synthesis and Processing

Transcriptional Regulation and Epigenetics

Protein Synthesis, Processing, and Regulation

The Nucleus

Protein Sorting and Transport

Mitochondria, Chloroplasts, and Peroxisomes

The Cytoskeleton and Cell Movement

The Plasma Membrane

Cell Walls, the Extracellular Matrix, and Cell Interactions

The Cell Cycle

Cell Death and Cell Renewal

Cancer

Filters

Binding of cAMP to the _ subunits of protein kinase A (PKA) leads to _ of that protein kinase.

Cholera toxin inhibits the ability of the $\alpha$ subunit of G_s to split GTP. If you treated cells with cholera toxin, the resulting effect would be _______ of adenylyl cyclase.

Protein kinase A regulates glycogen metabolism by _ glycogen synthase and _ glycogen phosphorylase.