Question 1

The deletion of the mreB gene in Escherichia coli results in __________.

Accepted Answer

A) rod-shaped cells 
B) crescent-shaped cells 
C) spherical cells 
D) spiral cells 
E) cells that look like bunches of grapes 
A) rod-shaped cells 
B) crescent-shaped cells 
C) spherical cells 
D) spiral cells 
E) cells that look like bunches of grapes

Question 2

A culture of Dictyostelium slime mold is prepared in which the myosin II gene is deleted. In which of the activity/ activities described below are these cells unable to participate?

Accepted Answer

A) separation of chromosomes during mitosis 
B) cell elongation 
C) cytokinesis 
D) separation of chromosomes during mitosis and cell elongation 
E) separation of chromosomes during mitosis and cytokinesis 
A) separation of chromosomes during mitosis 
B) cell elongation 
C) cytokinesis 
D) separation of chromosomes during mitosis and cell elongation 
E) separation of chromosomes during mitosis and cytokinesis

Question 3

Given that axons growing out of a neuron require the outward growth of microtubules to support the lengtheningaxon, what would be likely to happen to axons growing out from a neuron when they are exposed to colchicine or nocodazole?

Accepted Answer

A) Axons would grow more rapidly. 
B) Axonal outgrowth would cease. 
C) Axons would branch more often. 
D) Axonal outgrowth would change direction more frequently. 
E) There would be no change in axonal outgrowth. 
A) Axons would grow more rapidly. 
B) Axonal outgrowth would cease. 
C) Axons would branch more often. 
D) Axonal outgrowth would change direction more frequently. 
E) There would be no change in axonal outgrowth.

Question 4

A small zone of fluorescent microtubules in a cell is photobleached so that their fluorescent label gives off no light. Some time later fluorescence returns to the bleached zone in the cell. Which of the following is a possible explanation for the recovery of fluorescence in the region of the cell previously bleached?

Accepted Answer

A) the dynamics of the microtubules turning over in that bleached zone of the cell 
B) the growth of new microtubules into the bleached zone 
C) movement of microtubules through the bleached zone all of these choices 
D) the dynamics of the microtubules turning over in that bleached zone of the cell and the growth of new microtubules into the bleached zone 
E) all of these choices 
A) the dynamics of the microtubules turning over in that bleached zone of the cell 
B) the growth of new microtubules into the bleached zone 
C) movement of microtubules through the bleached zone all of these choices 
D) the dynamics of the microtubules turning over in that bleached zone of the cell and the growth of new microtubules into the bleached zone 
E) all of these choices

Question 5

What chemical below is known to bind to free actin monomers and block their incorporation into the polymer?

Accepted Answer

A) cytochalasins 
B) nocodazole 
C) phalloidin 
D) latrunculin 
E) phalloidin and latrunculin 
A) cytochalasins 
B) nocodazole 
C) phalloidin 
D) latrunculin 
E) phalloidin and latrunculin

Question 6

Which of the following would be the most direct method to label microtubules with a fluorescent dye?

Accepted Answer

A) injecting tubulin with a fluorescent dye 
B) attaching a fluorescently-labeled antibody to tubulin 
C) attaching a fluorescently-labeled antibody to actin 
D) inducing a cell to express the gene for tubulin that has been fused to the gene for GFP 
E) attaching a fluorescently-labeled antibody to tubulin and inducing a cell to express the gene for tubulin that has been fused to the gene for GFP 
A) injecting tubulin with a fluorescent dye 
B) attaching a fluorescently-labeled antibody to tubulin 
C) attaching a fluorescently-labeled antibody to actin 
D) inducing a cell to express the gene for tubulin that has been fused to the gene for GFP 
E) attaching a fluorescently-labeled antibody to tubulin and inducing a cell to express the gene for tubulin that has been fused to the gene for GFP

Question 7

What provides the energy that drives sarcomere contraction?

Accepted Answer

A) ATP 
B) ADP 
C) GTP 
D) GDP 
E) none of these choices 
A) ATP 
B) ADP 
C) GTP 
D) GDP 
E) none of these choices

Question 8

Muscle contracted to a size shorter than its resting length has less tension than one at resting length because:

Accepted Answer

A) Z discs will collide with thin filaments 
B) Z discs will collide with thick filaments 
C) H bands will widen 
D) A bands will widen 
E) none of these is a correct explanation for the reduced tension 
A) Z discs will collide with thin filaments 
B) Z discs will collide with thick filaments 
C) H bands will widen 
D) A bands will widen 
E) none of these is a correct explanation for the reduced tension

Question 9

You use an ionic detergent to extract materials from a cell. When you do, much of the mRNA stays behind with the cytoskeleton, which is not solubilized/depolymerized by this treatment. What do these results mean?

Accepted Answer

A) The cytoskeleton denatures in ionic detergents. 
B) The mRNA is solubilized by the ionic detergents. 
C) The mRNA is anchored to the cytoskeleton. 
D) The cytoplasm is anchored to the mRNA. 
E) The cytoskeleton is destabilized by the ionic detergent. 
A) The cytoskeleton denatures in ionic detergents. 
B) The mRNA is solubilized by the ionic detergents. 
C) The mRNA is anchored to the cytoskeleton. 
D) The cytoplasm is anchored to the mRNA. 
E) The cytoskeleton is destabilized by the ionic detergent.

Question 10

Which of the following treatments do/does NOT disassemble microtubules in living cells?

Accepted Answer

A) slightly elevated temperature 
B) hydrostatic pressure 
C) elevatedCa2+ion concentration 
D) colchicine or vinblastine treatment 
E) all of these choices disassemble microtubules in living cells 
A) slightly elevated temperature 
B) hydrostatic pressure 
C) elevatedCa2+ion concentration 
D) colchicine or vinblastine treatment 
E) all of these choices disassemble microtubules in living cells

Question 11

Which cytoskeletal element could be described as solid, thinner structures that are often organized into a branching network?

Accepted Answer

A) actin filaments 
B) microtubules 
C) intermediate filaments 
D) macrotubules 
E) minifilaments 
A) actin filaments 
B) microtubules 
C) intermediate filaments 
D) macrotubules 
E) minifilaments

Question 12

What happens to the Z line positioning after contraction of the sarcomere?

Accepted Answer

A) The distance between the Z lines does not change. 
B) The distance between the Z lines decreases. 
C) The distance between the Z lines increases. 
D) The Z lines disappear. 
E) The Z lines become curved. 
A) The distance between the Z lines does not change. 
B) The distance between the Z lines decreases. 
C) The distance between the Z lines increases. 
D) The Z lines disappear. 
E) The Z lines become curved.

Question 13

To which end of microtubules are tubulin subunits primarily added in vitro?

Accepted Answer

A) the minus end 
B) the N-terminal end 
C) the plus end 
D) the C-terminal end 
E) the 5'-end 
A) the minus end 
B) the N-terminal end 
C) the plus end 
D) the C-terminal end 
E) the 5'-end

Question 14

Which of the following is a plausible explanation for the fact that the chemical EGTA blocks microtubule disassembly?

Accepted Answer

A) EGTA binds to Ca2+ ions, which are known to induce microtubule depolymerization. 
B) EGTA binds to Mg2+ ions, which are known to induce microtubule depolymerization. 
C) EGTA binds to Ca2+ ions, which are known to induce microtubule polymerization. 
D) EGTA destroys Ca2+ ions, which are known to inhibit microtubule polymerization. 
E) EGTA destroys Mg2+ ions, which are known to inhibit microtubule polymerization. 
A) EGTA binds to Ca2+ ions, which are known to induce microtubule depolymerization. 
B) EGTA binds to Mg2+ ions, which are known to induce microtubule depolymerization. 
C) EGTA binds to Ca2+ ions, which are known to induce microtubule polymerization. 
D) EGTA destroys Ca2+ ions, which are known to inhibit microtubule polymerization. 
E) EGTA destroys Mg2+ ions, which are known to inhibit microtubule polymerization.

Question 15

How are proteins and neurotransmitters usually transported down the axon of a nerve cell?

Accepted Answer

A) individually by diffusion 
B) in groups of ten 
C) inside transport vesicles 
D) inside the Golgi complex 
E) tied individually to microtubules 
A) individually by diffusion 
B) in groups of ten 
C) inside transport vesicles 
D) inside the Golgi complex 
E) tied individually to microtubules

Question 16

Which property below is most characteristic of intermediate filaments?

Accepted Answer

A) elastic 
B) highly resistant to shrinkage 
C) springy 
D) ability to absorb mechanical stresses applied by the extracellular environment 
E) inflexible 
A) elastic 
B) highly resistant to shrinkage 
C) springy 
D) ability to absorb mechanical stresses applied by the extracellular environment 
E) inflexible

Question 17

What is a major influence in determining the organization and behavior of actin filaments inside cells?

Accepted Answer

A) axonemes 
B) tubulin 
C) actin-binding proteins 
D) dynein 
E) actin-binding proteins and dynein 
A) axonemes 
B) tubulin 
C) actin-binding proteins 
D) dynein 
E) actin-binding proteins and dynein

Question 18

After they have elongated, the cells of the neural epithelium become constricted at one end, causing them to become wedge shaped and leading the entire layer of cells to curve inward. What causes this constriction?

Accepted Answer

A) contraction of microtubules in the cytoplasm just above the basal cell membrane 
B) lengthening of microtubules in the cytoplasm just below the apical cell membrane 
C) contraction of a band of actin filaments that assemble in the cortical region of the cells just above the basal cell membrane 
D) contraction of a band of actin filaments that assemble in the cortical region of the cells just beneath the apical cell membrane 
E) shortening of microtubules in the cytoplasm just below the apical cell membrane 
A) contraction of microtubules in the cytoplasm just above the basal cell membrane 
B) lengthening of microtubules in the cytoplasm just below the apical cell membrane 
C) contraction of a band of actin filaments that assemble in the cortical region of the cells just above the basal cell membrane 
D) contraction of a band of actin filaments that assemble in the cortical region of the cells just beneath the apical cell membrane 
E) shortening of microtubules in the cytoplasm just below the apical cell membrane

Question 19

Which of the following non-muscle cell activities do NOT involve actin filaments often working in concert with myosin motors?

Accepted Answer

A) cytokinesis 
B) blood platelet activation 
C) vesicle trafficking 
D) red blood cells carrying oxygen 
E) changes in cell shape 
A) cytokinesis 
B) blood platelet activation 
C) vesicle trafficking 
D) red blood cells carrying oxygen 
E) changes in cell shape

Question 20

What end of a microtubule is associated with the centrosome?

Accepted Answer

A) the plus end 
B) the minus end 
C) the 5'-end 
D) the 3'-end 
E) the 0-end 
A) the plus end 
B) the minus end 
C) the 5'-end 
D) the 3'-end 
E) the 0-end

The deletion of the mreB gene in Escherichia coli results in __________.

A culture of Dictyostelium slime mold is prepared in which the myosin II gene is deleted. In which of the activity/ activities described below are these cells unable to participate?

Given that axons growing out of a neuron require the outward growth of microtubules to support the lengtheningaxon, what would be likely to happen to axons growing out from a neuron when they are exposed to colchicine or nocodazole?

What chemical below is known to bind to free actin monomers and block their incorporation into the polymer?

Which of the following would be the most direct method to label microtubules with a fluorescent dye?

What provides the energy that drives sarcomere contraction?

Muscle contracted to a size shorter than its resting length has less tension than one at resting length because:

You use an ionic detergent to extract materials from a cell. When you do, much of the mRNA stays behind with the cytoskeleton, which is not solubilized/depolymerized by this treatment. What do these results mean?

Which of the following treatments do/does NOT disassemble microtubules in living cells?

Which cytoskeletal element could be described as solid, thinner structures that are often organized into a branching network?

What happens to the Z line positioning after contraction of the sarcomere?

To which end of microtubules are tubulin subunits primarily added in vitro?

Which of the following is a plausible explanation for the fact that the chemical EGTA blocks microtubule disassembly?

How are proteins and neurotransmitters usually transported down the axon of a nerve cell?

Which property below is most characteristic of intermediate filaments?

What is a major influence in determining the organization and behavior of actin filaments inside cells?

After they have elongated, the cells of the neural epithelium become constricted at one end, causing them to become wedge shaped and leading the entire layer of cells to curve inward. What causes this constriction?

Which of the following non-muscle cell activities do NOT involve actin filaments often working in concert with myosin motors?

What end of a microtubule is associated with the centrosome?

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 Nature of the Gene and the Genome

Gene Expression: From Transcription to Translation

Control of Gene Expression

Dna Replication and Repair

Cellular Reproduction

Cell Signaling and Signal Transduction: Communication Between Cells

Cancer

The Immune Response

Techniques in Cell and Molecular Biology

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Exam 9: The Cytoskeleton and Cell Motility

The deletion of the mreB gene in Escherichia coli results in __________.

A culture of Dictyostelium slime mold is prepared in which the myosin II gene is deleted. In which of the activity/ activities described below are these cells unable to participate?

Given that axons growing out of a neuron require the outward growth of microtubules to support the lengtheningaxon, what would be likely to happen to axons growing out from a neuron when they are exposed to colchicine or nocodazole?

What chemical below is known to bind to free actin monomers and block their incorporation into the polymer?

Which of the following would be the most direct method to label microtubules with a fluorescent dye?

What provides the energy that drives sarcomere contraction?

Muscle contracted to a size shorter than its resting length has less tension than one at resting length because:

You use an ionic detergent to extract materials from a cell. When you do, much of the mRNA stays behind with the cytoskeleton, which is not solubilized/depolymerized by this treatment. What do these results mean?

Which of the following treatments do/does NOT disassemble microtubules in living cells?

Which cytoskeletal element could be described as solid, thinner structures that are often organized into a branching network?

What happens to the Z line positioning after contraction of the sarcomere?

To which end of microtubules are tubulin subunits primarily added in vitro?

Which of the following is a plausible explanation for the fact that the chemical EGTA blocks microtubule disassembly?

How are proteins and neurotransmitters usually transported down the axon of a nerve cell?

Which property below is most characteristic of intermediate filaments?

What is a major influence in determining the organization and behavior of actin filaments inside cells?

After they have elongated, the cells of the neural epithelium become constricted at one end, causing them to become wedge shaped and leading the entire layer of cells to curve inward. What causes this constriction?

Which of the following non-muscle cell activities do NOT involve actin filaments often working in concert with myosin motors?

What end of a microtubule is associated with the centrosome?

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 Nature of the Gene and the Genome

Gene Expression: From Transcription to Translation

Control of Gene Expression

Dna Replication and Repair

Cellular Reproduction

Cell Signaling and Signal Transduction: Communication Between Cells

Cancer

The Immune Response

Techniques in Cell and Molecular Biology

Filters