Question 1

Which steroid hormone(s) is(are) not secreted by the gonads?

Accepted Answer

A)  Corticosteroids 
B)  Progesterone 
C)  Estrogen 
D)  Testosterone 
A)  Corticosteroids 
B)  Progesterone 
C)  Estrogen 
D)  Testosterone

Question 2

Which statement about protein kinase A (PKA) is false?

Accepted Answer

A)  In the inactive state, PKA exists as a tetramer of two regulatory (R) and two catalytic (
C)  subunits. 
B)  PKA binds a total of four molecules of cAMP, one on each of the four subunits. 
C)  PKA binds a total of four molecules, two molecules on each of the two regulatory (R) subunits. 
D)  Once activated, the catalytic (
C)  subunits dissociate and activate target molecules. 
A)  In the inactive state, PKA exists as a tetramer of two regulatory (R) and two catalytic (
C)  subunits. 
B)  PKA binds a total of four molecules of cAMP, one on each of the four subunits. 
C)  PKA binds a total of four molecules, two molecules on each of the two regulatory (R) subunits. 
D)  Once activated, the catalytic (
C)  subunits dissociate and activate target molecules.

Question 3

Receptor tyrosine kinases represent critical molecules involved in growth and differentiation though phosphorylation of target substrates on tyrosine residues. Which structural feature is not common among all receptor tyrosine kinases?

Accepted Answer

A)  An N-terminal extracellular ligand-binding domain 
B)  A single polypeptide 
C)  A cytosolic C-terminal domain with tyrosine kinase activity 
D)  A single transmembrane $\alpha$helix 
A)  An N-terminal extracellular ligand-binding domain 
B)  A single polypeptide 
C)  A cytosolic C-terminal domain with tyrosine kinase activity 
D)  A single transmembrane $\alpha$helix

Question 4

Expression of the immediate early genes triggers the expression of a battery of other downstream genes called _______.

Accepted Answer

secondary

Question 5

What is the role of$\beta$-arrestin in mediating crosstalk signaling between G protein-coupled receptors (GPCR) and ERK signaling?

Accepted Answer

Crosstalk from G-protein receptors and E

Question 6

Signaling by cadherins 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 7

Caffeine is a phosphodiesterase inhibitor. What affect would caffeine treatment have on cells growing in culture?

Accepted Answer

Phosphodiesterase converts cAM

Question 8

Which statement about G protein signaling is false?

Accepted Answer

A)  Hormone binding induces an interaction of the receptor with the G protein, stimulating the release of GDP and the exchange of GTP on the $\alpha$subunit. 
B)  Once activated, the GTP-bound $\alpha$ subunit dissociates from $\beta$$\gamma$ and interacts with its target. 
C)  Activity of the $\alpha$ subunit is terminated by the hydrolysis of GTP to GDP. 
D)  The $\alpha$ subunit becomes deactivated when the hormone dissociates from the receptor. 
A)  Hormone binding induces an interaction of the receptor with the G protein, stimulating the release of GDP and the exchange of GTP on the $\alpha$subunit. 
B)  Once activated, the GTP-bound $\alpha$ subunit dissociates from $\beta$$\gamma$ and interacts with its target. 
C)  Activity of the $\alpha$ subunit is terminated by the hydrolysis of GTP to GDP. 
D)  The $\alpha$ subunit becomes deactivated when the hormone dissociates from the receptor.

Question 9

What are the three steps by which receptor tyrosine kinases typically convey an extracellular signal to another intracellular enzyme?

Accepted Answer

(1) Dimerization of receptors in the pre

Question 10

In the absence of cAMP, what is the status of protein kinase A?

Accepted Answer

It is in the cytoplasm in a te

Question 11

Enkephalins and endorphins bind to the same receptors in the brain as

Accepted Answer

A)  nerve growth factor. 
B)  aspirin. 
C)  morphine. 
D)  acetylcholine. 
A)  nerve growth factor. 
B)  aspirin. 
C)  morphine. 
D)  acetylcholine.

Question 12

Mutated oncogenic Ras proteins usually

Accepted Answer

A)  cleave GTP more rapidly than normal. 
B)  fail to bind Raf. 
C)  cleave GTP less rapidly than normal. 
D)  bind GAP more tightly than normal. 
A)  cleave GTP more rapidly than normal. 
B)  fail to bind Raf. 
C)  cleave GTP less rapidly than normal. 
D)  bind GAP more tightly than normal.

Question 13

TGF-$\beta$ signaling leads to the activation of the Smad family of transcription factors.

Accepted Answer

A) True 
 B)False

Question 14

The GTP on the G protein that is linked to adenylyl cyclase is split to GDP and Pi

Accepted Answer

A)  in the inactive state. 
B)  in the process of subunit separation. 
C)  upon activation by the receptor. 
D)  by the active $\alpha$ subunit. 
A)  in the inactive state. 
B)  in the process of subunit separation. 
C)  upon activation by the receptor. 
D)  by the active $\alpha$ subunit.

Question 15

The binding of Hedgehog to the receptor Patched releases a transcription factor from actin microfilaments that enters the nucleus and turns on genes.

Accepted Answer

A) True 
 B)False

Question 16

The phosphorylated ERK kinase moves into the nucleus and phosphorylates the transcription factor _______, which binds to serum response elements in a complex with _______ and turns on a set of genes called the _______ genes.

Accepted Answer

Elk-1; SRF (serum re

Question 17

What are the hallmarks of the first steps in signaling through receptor tyrosine kinases?

Accepted Answer

Receptor tyrosine kinases span the plasm

Question 18

Neurotransmitters act by binding to receptors that are

Accepted Answer

A)  ligand-gated ion channels. 
B)  located in the cytoplasm. 
C)  tyrosine-kinase receptors. 
D)  not coupled to G proteins. 
A)  ligand-gated ion channels. 
B)  located in the cytoplasm. 
C)  tyrosine-kinase receptors. 
D)  not coupled to G proteins.

Question 19

Cytokine receptors frequently form dimers upon ligand binding, and these can be heterodimers or homodimers. Explain how this ability of the receptors to form different combinations of dimers allows three unique cytokines, each with a unique action, to arise from only two cytokine receptors.

Accepted Answer

If dimerization is required, then the tw

Question 20

The first step in growth factor pathway activation is

Accepted Answer

A)  receptor dimerization. 
B)  receptor phosphorylation. 
C)  Ras activation. 
D)  the binding of SH2-containing proteins. 
A)  receptor dimerization. 
B)  receptor phosphorylation. 
C)  Ras activation. 
D)  the binding of SH2-containing proteins.

Which steroid hormone(s) is(are) not secreted by the gonads?

Which statement about protein kinase A (PKA) is false?

Receptor tyrosine kinases represent critical molecules involved in growth and differentiation though phosphorylation of target substrates on tyrosine residues. Which structural feature is not common among all receptor tyrosine kinases?

Expression of the immediate early genes triggers the expression of a battery of other downstream genes called _______.

What is the role of $\beta$ -arrestin in mediating crosstalk signaling between G protein-coupled receptors (GPCR) and ERK signaling?

Signaling by cadherins is an example of _______ signaling.

Caffeine is a phosphodiesterase inhibitor. What affect would caffeine treatment have on cells growing in culture?

Which statement about G protein signaling is false?

What are the three steps by which receptor tyrosine kinases typically convey an extracellular signal to another intracellular enzyme?

In the absence of cAMP, what is the status of protein kinase A?

Enkephalins and endorphins bind to the same receptors in the brain as

Mutated oncogenic Ras proteins usually

TGF- $\beta$ signaling leads to the activation of the Smad family of transcription factors.

The GTP on the G protein that is linked to adenylyl cyclase is split to GDP and P_i

The binding of Hedgehog to the receptor Patched releases a transcription factor from actin microfilaments that enters the nucleus and turns on genes.

The phosphorylated ERK kinase moves into the nucleus and phosphorylates the transcription factor ___, which binds to serum response elements in a complex with _ and turns on a set of genes called the _____ genes.

What are the hallmarks of the first steps in signaling through receptor tyrosine kinases?

Neurotransmitters act by binding to receptors that are

Cytokine receptors frequently form dimers upon ligand binding, and these can be heterodimers or homodimers. Explain how this ability of the receptors to form different combinations of dimers allows three unique cytokines, each with a unique action, to arise from only two cytokine receptors.

The first step in growth factor pathway activation is

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

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Exam 17: Cell Signaling

Which steroid hormone(s) is(are) not secreted by the gonads?

Which statement about protein kinase A (PKA) is false?

Receptor tyrosine kinases represent critical molecules involved in growth and differentiation though phosphorylation of target substrates on tyrosine residues. Which structural feature is not common among all receptor tyrosine kinases?

Expression of the immediate early genes triggers the expression of a battery of other downstream genes called _______.

What is the role of β\betaβ -arrestin in mediating crosstalk signaling between G protein-coupled receptors (GPCR) and ERK signaling?

Signaling by cadherins is an example of _______ signaling.

Caffeine is a phosphodiesterase inhibitor. What affect would caffeine treatment have on cells growing in culture?

Which statement about G protein signaling is false?

What are the three steps by which receptor tyrosine kinases typically convey an extracellular signal to another intracellular enzyme?

In the absence of cAMP, what is the status of protein kinase A?

Enkephalins and endorphins bind to the same receptors in the brain as

Mutated oncogenic Ras proteins usually

TGF- β\betaβ signaling leads to the activation of the Smad family of transcription factors.

The GTP on the G protein that is linked to adenylyl cyclase is split to GDP and Pi

The binding of Hedgehog to the receptor Patched releases a transcription factor from actin microfilaments that enters the nucleus and turns on genes.

The phosphorylated ERK kinase moves into the nucleus and phosphorylates the transcription factor _______, which binds to serum response elements in a complex with _______ and turns on a set of genes called the _______ genes.

What are the hallmarks of the first steps in signaling through receptor tyrosine kinases?

Neurotransmitters act by binding to receptors that are

Cytokine receptors frequently form dimers upon ligand binding, and these can be heterodimers or homodimers. Explain how this ability of the receptors to form different combinations of dimers allows three unique cytokines, each with a unique action, to arise from only two cytokine receptors.

The first step in growth factor pathway activation is

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

What is the role of $\beta$ -arrestin in mediating crosstalk signaling between G protein-coupled receptors (GPCR) and ERK signaling?

TGF- $\beta$ signaling leads to the activation of the Smad family of transcription factors.

The GTP on the G protein that is linked to adenylyl cyclase is split to GDP and P_i

The phosphorylated ERK kinase moves into the nucleus and phosphorylates the transcription factor ___, which binds to serum response elements in a complex with _ and turns on a set of genes called the _____ genes.