Question 1

What happens to cells if the receptors are degraded once they are internalized?

Accepted Answer

A) The cells are able to make a magnified response to the same stimulus from the ligand in question. 
B) The cells permanently lose sensitivity for the ligand in question. 
C) The cells lose,at least temporarily,sensitivity for the ligand in question. 
D) The cells remain sensitive to the ligand in question. 
E) The cells expand. 
A) The cells are able to make a magnified response to the same stimulus from the ligand in question. 
B) The cells permanently lose sensitivity for the ligand in question. 
C) The cells lose,at least temporarily,sensitivity for the ligand in question. 
D) The cells remain sensitive to the ligand in question. 
E) The cells expand. C

Question 2

Which heterotrimeric G proteins are less well characterized than the other G protein families and have had their inappropriate activation associated with excessive cell proliferation and malignant transformations?

Accepted Answer

A) Gs family 
B) Gq family 
C) Gi family 
D) G12/13 family 
E) Gr family 
A) Gs family 
B) Gq family 
C) Gi family 
D) G12/13 family 
E) Gr family D

Question 3

The overall process in which information carried by extracellular messenger molecules is translated into changes that occur inside the cell is called ___________.

Accepted Answer

A) signal digestion 
B) signal destruction 
C) signal interaction 
D) signal transduction 
E) signal induction 
A) signal digestion 
B) signal destruction 
C) signal interaction 
D) signal transduction 
E) signal induction D

Question 4

Which molecule below is unlikely to act as either a neurotransmitter or hormone?

Accepted Answer

A) glucose 
B) glycine 
C) dopamine 
D) eicosanoids 
E) thyroid hormone 
A) glucose 
B) glycine 
C) dopamine 
D) eicosanoids 
E) thyroid hormone

Question 5

Why do colds cause us to lose some of our appreciation for the taste of food?

Accepted Answer

A) The symptoms of colds interfere with the stimuli reaching the taste bud receptors,thus dulling the perception of taste. 
B) The symptoms of colds prevent stimuli from reaching olfactory neurons efficiently,thus dulling the perception of taste. 
C) Cold viruses raise the firing threshold of olfactory neurons,thus dulling the perception of taste. 
D) Cold viruses lower the firing threshold of olfactory neurons,thus dulling the perception of taste. 
E) Cold viruses denature olfactory neurons,thus dulling the perception of taste. 
A) The symptoms of colds interfere with the stimuli reaching the taste bud receptors,thus dulling the perception of taste. 
B) The symptoms of colds prevent stimuli from reaching olfactory neurons efficiently,thus dulling the perception of taste. 
C) Cold viruses raise the firing threshold of olfactory neurons,thus dulling the perception of taste. 
D) Cold viruses lower the firing threshold of olfactory neurons,thus dulling the perception of taste. 
E) Cold viruses denature olfactory neurons,thus dulling the perception of taste.

Question 6

What does the interaction between arrestin and clathrin promote?

Accepted Answer

A) the uptake of free hormone 
B) the uptake of phosphorylated GPCRs into the cell by exocytosis 
C) the uptake of phosphorylated GPCRs into the cell by endocytosis 
D) the expulsion of phosphorylated GPCRs from the cell by exocytosis 
E) the secretion of GPCRs 
A) the uptake of free hormone 
B) the uptake of phosphorylated GPCRs into the cell by exocytosis 
C) the uptake of phosphorylated GPCRs into the cell by endocytosis 
D) the expulsion of phosphorylated GPCRs from the cell by exocytosis 
E) the secretion of GPCRs

Question 7

To which amino acid is nitric oxide added,altering the activity,turnover and/or interactions of proteins like hemoglobin,Ras,ryanodine channels and caspases?

Accepted Answer

A) alanine 
B) cysteine 
C) methionine 
D) asparagine 
E) phenylalanine 
A) alanine 
B) cysteine 
C) methionine 
D) asparagine 
E) phenylalanine

Question 8

Which heterotrimeric G proteins couple receptors to adenylyl cyclase via the activation of GTP-bound G $\alpha$  subunits?

Accepted Answer

A) Gs family 
B) Gq family 
C) Gi family 
D) G12/13 family 
E) Gr family 
A) Gs family 
B) Gq family 
C) Gi family 
D) G12/13 family 
E) Gr family

Question 9

Where are steroid receptors generally located and where do they bind the steroid hormone once it enters the cell?

Accepted Answer

A) They are located and bind the steroids in the cytoplasm. 
B) They are located and bind the steroids in the middle of the cell membrane. 
C) They are located and bind the steroids on the extracellular membrane surface. 
D) They are located and bind the steroids on the intracellular membrane surface. 
E) The receptors are located in the cytoplasm but they bind their ligands in the lysosomes. 
A) They are located and bind the steroids in the cytoplasm. 
B) They are located and bind the steroids in the middle of the cell membrane. 
C) They are located and bind the steroids on the extracellular membrane surface. 
D) They are located and bind the steroids on the intracellular membrane surface. 
E) The receptors are located in the cytoplasm but they bind their ligands in the lysosomes.

Question 10

Which of the following processes is not regulated by eicosanoids?

Accepted Answer

A) pain 
B) inflammation 
C) blood pressure 
D) blood clotting 
E) neurotransmission 
A) pain 
B) inflammation 
C) blood pressure 
D) blood clotting 
E) neurotransmission

Question 11

What molecule is responsible for activating Rsk-2?

Accepted Answer

A) PKA 
B) CREB 
C) MAPKK 
D) MAPK 
E) cAMP 
A) PKA 
B) CREB 
C) MAPKK 
D) MAPK 
E) cAMP

Question 12

How is caspase-activated DNase (CAD)activated?

Accepted Answer

A) A caspase cleaves CAD,activating it. 
B) A caspase cleaves an activator of CAD,turning it on and causing it to activate CAD. 
C) A caspase cleaves a CAD inhibitor,relieving the CAD of inhibition. 
D) A caspase binds to CAD allosterically,activating it. 
E) None of these are correct. 
A) A caspase cleaves CAD,activating it. 
B) A caspase cleaves an activator of CAD,turning it on and causing it to activate CAD. 
C) A caspase cleaves a CAD inhibitor,relieving the CAD of inhibition. 
D) A caspase binds to CAD allosterically,activating it. 
E) None of these are correct.

Question 13

What kinds of responses are not initiated when signals traveling down signaling pathways reach their target proteins,which are usually involved in basic cellular processes?

Accepted Answer

A) a change in gene expression 
B) a change in ion permeability 
C) cessation of DNA synthesis and degradation of DNA 
D) the death of the cell 
E) an alteration of the activity of metabolic enzymes 
A) a change in gene expression 
B) a change in ion permeability 
C) cessation of DNA synthesis and degradation of DNA 
D) the death of the cell 
E) an alteration of the activity of metabolic enzymes

Question 14

How is the distribution of free calcium ions in the living cell detected?

Accepted Answer

A) fluorescent probes that emit light in the presence of calcium ions 
B) antibodies bound to ferritin 
C) an electron microscope 
D) autoradiography and the distribution of radioisotope 
E) NMR imaging 
A) fluorescent probes that emit light in the presence of calcium ions 
B) antibodies bound to ferritin 
C) an electron microscope 
D) autoradiography and the distribution of radioisotope 
E) NMR imaging

Question 15

Why did the smooth muscle in cultured strips of aorta not respond to acetylcholine by relaxing,while the smooth muscle of aortic rings did?

Accepted Answer

A) Smooth muscle cells in aortic strips are physically incapable of relaxing under any circumstances. 
B) Acetylcholine in the strips could not penetrate to the muscle cells while in the rings it could. 
C) Smooth muscle cells in aortic rings express acetylcholine receptors,while those in strips do not. 
D) The delicate endothelial layer in aortal strips had been rubbed away during dissection,while in aortal rings it remained intact. 
E) The endothelial layer in aortal strips was abnormally thickened,while in aortal rings it was not. 
A) Smooth muscle cells in aortic strips are physically incapable of relaxing under any circumstances. 
B) Acetylcholine in the strips could not penetrate to the muscle cells while in the rings it could. 
C) Smooth muscle cells in aortic rings express acetylcholine receptors,while those in strips do not. 
D) The delicate endothelial layer in aortal strips had been rubbed away during dissection,while in aortal rings it remained intact. 
E) The endothelial layer in aortal strips was abnormally thickened,while in aortal rings it was not.

Question 16

Arrestin binding to GPCRs __________.

Accepted Answer

A) causes the binding of additional G proteins 
B) prevents further activation of additional G proteins 
C) causes denaturation of G proteins 
D) stabilizes G proteins 
E) stabilizes GPCRs 
A) causes the binding of additional G proteins 
B) prevents further activation of additional G proteins 
C) causes denaturation of G proteins 
D) stabilizes G proteins 
E) stabilizes GPCRs

Question 17

The _________ pathway of apoptosis is one in which external stimuli activate apoptosis via a signaling pathway.

Accepted Answer

A) extrinsic 
B) external 
C) intrinsic 
D) peripheral 
E) integral 
A) extrinsic 
B) external 
C) intrinsic 
D) peripheral 
E) integral

Question 18

In which organism below has calmodulin not been found?

Accepted Answer

A) plants 
B) animals 
C) bacteria 
D) yeasts 
E) humans 
A) plants 
B) animals 
C) bacteria 
D) yeasts 
E) humans

Question 19

What is activated by calcium ions entering an egg cell just after fertilization?

Accepted Answer

A) protein kinase A 
B) insulin 
C) cyclin-dependent kinases that drive the zygote toward its first mitotic division 
D) cyclin-dependent kinases that drive the zygote toward its first meiotic division 
E) glucagon-dependent kinases that drive the zygote toward its first mitotic division 
A) protein kinase A 
B) insulin 
C) cyclin-dependent kinases that drive the zygote toward its first mitotic division 
D) cyclin-dependent kinases that drive the zygote toward its first meiotic division 
E) glucagon-dependent kinases that drive the zygote toward its first mitotic division

Question 20

How do cells in the body of a multicellular organism usually communicate with each other?

Accepted Answer

A) intracellular messenger molecules 
B) direct connection by cells through long projections 
C) extracellular messenger molecules 
D) electrical signals between cells 
E) ion transport between cells 
A) intracellular messenger molecules 
B) direct connection by cells through long projections 
C) extracellular messenger molecules 
D) electrical signals between cells 
E) ion transport between cells

What happens to cells if the receptors are degraded once they are internalized?

Which heterotrimeric G proteins are less well characterized than the other G protein families and have had their inappropriate activation associated with excessive cell proliferation and malignant transformations?

The overall process in which information carried by extracellular messenger molecules is translated into changes that occur inside the cell is called ___________.

Which molecule below is unlikely to act as either a neurotransmitter or hormone?

Why do colds cause us to lose some of our appreciation for the taste of food?

What does the interaction between arrestin and clathrin promote?

To which amino acid is nitric oxide added,altering the activity,turnover and/or interactions of proteins like hemoglobin,Ras,ryanodine channels and caspases?

Which heterotrimeric G proteins couple receptors to adenylyl cyclase via the activation of GTP-bound G _$\alpha$ subunits?

Where are steroid receptors generally located and where do they bind the steroid hormone once it enters the cell?

Which of the following processes is not regulated by eicosanoids?

What molecule is responsible for activating Rsk-2?

How is caspase-activated DNase (CAD)activated?

What kinds of responses are not initiated when signals traveling down signaling pathways reach their target proteins,which are usually involved in basic cellular processes?

How is the distribution of free calcium ions in the living cell detected?

Why did the smooth muscle in cultured strips of aorta not respond to acetylcholine by relaxing,while the smooth muscle of aortic rings did?

Arrestin binding to GPCRs __________.

The _________ pathway of apoptosis is one in which external stimuli activate apoptosis via a signaling pathway.

In which organism below has calmodulin not been found?

What is activated by calcium ions entering an egg cell just after fertilization?

How do cells in the body of a multicellular organism usually communicate with each other?

Introduction to the Study of Cell and Molecular Biology

The Chemical Basis of Life

Bioenergetics, Enzymes, and Metabolism

The Structure and Function of the Plasma Membrane

Aerobic Respiration and the Mitochondrion

Photosynthesis and the Chloroplast

Interactions Between Cells and Their Environment

Cytoplasmic Membrane Systems: Structure, Function, and Membrane Trafficking

The Cytoskeleton and Cell Motility

The Nature of the Gene and the Genome

Gene Expression: From Transcription to Translation

Control of Gene Expression

Dna Replication and Repair

Cellular Reproduction

Cancer

The Immune Response

Techniques in Cell and Molecular Biology

Filters

Exam 15: Cell Signaling and Signal Transduction: Communication Between Cells

What happens to cells if the receptors are degraded once they are internalized?

Which heterotrimeric G proteins are less well characterized than the other G protein families and have had their inappropriate activation associated with excessive cell proliferation and malignant transformations?

The overall process in which information carried by extracellular messenger molecules is translated into changes that occur inside the cell is called ___________.

Which molecule below is unlikely to act as either a neurotransmitter or hormone?

Why do colds cause us to lose some of our appreciation for the taste of food?

What does the interaction between arrestin and clathrin promote?

To which amino acid is nitric oxide added,altering the activity,turnover and/or interactions of proteins like hemoglobin,Ras,ryanodine channels and caspases?

Which heterotrimeric G proteins couple receptors to adenylyl cyclase via the activation of GTP-bound G α\alphaα subunits?

Where are steroid receptors generally located and where do they bind the steroid hormone once it enters the cell?

Which of the following processes is not regulated by eicosanoids?

What molecule is responsible for activating Rsk-2?

How is caspase-activated DNase (CAD)activated?

What kinds of responses are not initiated when signals traveling down signaling pathways reach their target proteins,which are usually involved in basic cellular processes?

How is the distribution of free calcium ions in the living cell detected?

Why did the smooth muscle in cultured strips of aorta not respond to acetylcholine by relaxing,while the smooth muscle of aortic rings did?

Arrestin binding to GPCRs __________.

The _________ pathway of apoptosis is one in which external stimuli activate apoptosis via a signaling pathway.

In which organism below has calmodulin not been found?

What is activated by calcium ions entering an egg cell just after fertilization?

How do cells in the body of a multicellular organism usually communicate with each other?

Introduction to the Study of Cell and Molecular Biology

The Chemical Basis of Life

Bioenergetics, Enzymes, and Metabolism

The Structure and Function of the Plasma Membrane

Aerobic Respiration and the Mitochondrion

Photosynthesis and the Chloroplast

Interactions Between Cells and Their Environment

Cytoplasmic Membrane Systems: Structure, Function, and Membrane Trafficking

The Cytoskeleton and Cell Motility

The Nature of the Gene and the Genome

Gene Expression: From Transcription to Translation

Control of Gene Expression

Dna Replication and Repair

Cellular Reproduction

Cancer

The Immune Response

Techniques in Cell and Molecular Biology

Filters

Which heterotrimeric G proteins couple receptors to adenylyl cyclase via the activation of GTP-bound G _$\alpha$ subunits?