Question 1

The role of Ca2+ in the control of muscle contraction is to

Accepted Answer

A)  cause depolarization of the T tubule system. 
B)  initiate changes in protein conformation that expose myosin-binding sites on actin. 
C)  change the conformation of myosin heads,thus causing microfilaments to slide past each other. 
D)  bind to tropomyosin and break actin-myosin cross-bridges. 
E)  block the ATP-binding site on myosin heads,enabling muscles to relax. 
A)  cause depolarization of the T tubule system. 
B)  initiate changes in protein conformation that expose myosin-binding sites on actin. 
C)  change the conformation of myosin heads,thus causing microfilaments to slide past each other. 
D)  bind to tropomyosin and break actin-myosin cross-bridges. 
E)  block the ATP-binding site on myosin heads,enabling muscles to relax. B

Question 2

Cardiac muscle differs from both smooth and skeletal muscle in that

Accepted Answer

A)  its actin and myosin show no repeating pattern of arrangement when viewed under a microscope. 
B)  neighboring cells in cardiac muscle are electrically coupled by gap junctions. 
C)  its contractions are not explained by the sliding filament theory of muscular contraction. 
D)  contractions of cardiac muscle are not due to Ca2+ influx into the sarcoplasm. 
E)  its cells are multinucleated. 
A)  its actin and myosin show no repeating pattern of arrangement when viewed under a microscope. 
B)  neighboring cells in cardiac muscle are electrically coupled by gap junctions. 
C)  its contractions are not explained by the sliding filament theory of muscular contraction. 
D)  contractions of cardiac muscle are not due to Ca2+ influx into the sarcoplasm. 
E)  its cells are multinucleated. B

Question 3

Exoskeletons of lobsters are composed of

Accepted Answer

A)  chitin and calcium-containing minerals. 
B)  collagen and calcium-containing minerals. 
C)  chitin and cartilage. 
D)  collagen and cartilage. 
E)  chitin,collagen,and calcium-containing minerals. 
A)  chitin and calcium-containing minerals. 
B)  collagen and calcium-containing minerals. 
C)  chitin and cartilage. 
D)  collagen and cartilage. 
E)  chitin,collagen,and calcium-containing minerals. A

Question 4

Which structure is absent in cells of a fish electric organ?

Accepted Answer

A)  Sarcomere 
B)  Nucleus 
C)  Mitochondria 
D)  Neuromuscular junction 
E)  Both a and d 
A)  Sarcomere 
B)  Nucleus 
C)  Mitochondria 
D)  Neuromuscular junction 
E)  Both a and d

Question 5

To maintain high efficiency and greater power output with increasing wing beat frequencies,insect flight muscles have evolved

Accepted Answer

A)  a high ratio of muscle contractions to excitation events. 
B)  a high ratio of actin to myosin. 
C)  a nonsliding filament contraction mechanism. 
D)  fast T tubules. 
E)  gap junctions. 
A)  a high ratio of muscle contractions to excitation events. 
B)  a high ratio of actin to myosin. 
C)  a nonsliding filament contraction mechanism. 
D)  fast T tubules. 
E)  gap junctions.

Question 6

Which statement about skeletal systems is true?

Accepted Answer

A)  An exoskeleton consists mostly of cartilage. 
B)  A hydrostatic skeleton cannot be used for locomotion. 
C)  An exoskeleton can continue to grow once it is laid down. 
D)  An external skeleton must remain flexible,so it never includes calcium-containing minerals,as bones do. 
E)  Bones in an endoskeleton are constantly undergoing change and remodeling. 
A)  An exoskeleton consists mostly of cartilage. 
B)  A hydrostatic skeleton cannot be used for locomotion. 
C)  An exoskeleton can continue to grow once it is laid down. 
D)  An external skeleton must remain flexible,so it never includes calcium-containing minerals,as bones do. 
E)  Bones in an endoskeleton are constantly undergoing change and remodeling.

Question 7

Which is not one of the systems that supplies muscles with the ATP needed for contraction?

Accepted Answer

A)  Immediate system 
B)  Gluconeogenesis system 
C)  Glycolytic system 
D)  Oxidative system 
E)  Both a and c 
A)  Immediate system 
B)  Gluconeogenesis system 
C)  Glycolytic system 
D)  Oxidative system 
E)  Both a and c

Question 8

Refer to the diagram below.Which statement based on the diagram is true?

Accepted Answer

A)  Structure 1 has ATPase activity. 
B)  Structure 2 blocks sites where myosin can bind. 
C)  Structure 3 has one subunit that binds myosin. 
D)  Structure 4 shortens in length as the sarcomere contracts. 
E)  Structure 5 binds calcium. 
A)  Structure 1 has ATPase activity. 
B)  Structure 2 blocks sites where myosin can bind. 
C)  Structure 3 has one subunit that binds myosin. 
D)  Structure 4 shortens in length as the sarcomere contracts. 
E)  Structure 5 binds calcium.

Question 9

Shot-putters competing in track and field events need short,intense bursts of energy,but they tend to be quickly fatigued by the activity.An examination of the muscles used in this sport would show that they

Accepted Answer

A)  have substantial reserves of fuel. 
B)  have low levels of ATPase activity. 
C)  are well-supplied with blood vessels. 
D)  have many mitochondria. 
E)  can develop tension quickly. 
A)  have substantial reserves of fuel. 
B)  have low levels of ATPase activity. 
C)  are well-supplied with blood vessels. 
D)  have many mitochondria. 
E)  can develop tension quickly.

Question 10

The three systems by which muscles obtain ATP

Accepted Answer

A)  differ in the capacity and rate at which they produce ATP. 
B)  rely on the large amounts of ATP stored in muscle. 
C)  produce similar amounts of ATP. 
D)  rely on reactions within mitochondria. 
E)  have similar time courses. 
A)  differ in the capacity and rate at which they produce ATP. 
B)  rely on the large amounts of ATP stored in muscle. 
C)  produce similar amounts of ATP. 
D)  rely on reactions within mitochondria. 
E)  have similar time courses.

Question 11

An apodeme is

Accepted Answer

A)  an external extension of an exoskeleton. 
B)  an internal extension of an exoskeleton. 
C)  a ligament. 
D)  a tendon. 
E)  a structural element of hydroskeletons. 
A)  an external extension of an exoskeleton. 
B)  an internal extension of an exoskeleton. 
C)  a ligament. 
D)  a tendon. 
E)  a structural element of hydroskeletons.

Question 12

"_______" is the term used for the state of the adductor muscle of a mollusk as it maintains a contraction for an extended period of time.

Accepted Answer

A)  Fix 
B)  Catch 
C)  Seal 
D)  Intercalate 
E)  Latch 
A)  Fix 
B)  Catch 
C)  Seal 
D)  Intercalate 
E)  Latch

Question 13

A sarcomere is best described as a

Accepted Answer

A)  moveable structural unit within a myofibril bounded by H zones. 
B)  fixed structural unit within a myofibril bounded by Z lines. 
C)  fixed structural unit within a myofibril bounded by A bands. 
D)  moveable structural unit within a myofibril bounded by Z lines. 
E)  collection of myofibrils. 
A)  moveable structural unit within a myofibril bounded by H zones. 
B)  fixed structural unit within a myofibril bounded by Z lines. 
C)  fixed structural unit within a myofibril bounded by A bands. 
D)  moveable structural unit within a myofibril bounded by Z lines. 
E)  collection of myofibrils.

Question 14

What allows an earthworm to move through soil?

Accepted Answer

A)  Antagonistic pairs of muscles that pull in opposition to one another using elements of an endoskeleton 
B)  Alternating contractions of circular and longitudinal muscles that push against elements of an endoskeleton 
C)  Contracting muscles attached to apodemes of an exoskeleton 
D)  Contractions of muscles that increase pressure on body fluids to extend the body forward 
E)  Shifting of body fluids from one compartment to another 
A)  Antagonistic pairs of muscles that pull in opposition to one another using elements of an endoskeleton 
B)  Alternating contractions of circular and longitudinal muscles that push against elements of an endoskeleton 
C)  Contracting muscles attached to apodemes of an exoskeleton 
D)  Contractions of muscles that increase pressure on body fluids to extend the body forward 
E)  Shifting of body fluids from one compartment to another

Question 15

The striated appearance of skeletal muscle is due to the

Accepted Answer

A)  dark color of myosin. 
B)  multiple nuclei per fiber. 
C)  regular arrangement of filaments. 
D)  dense array of microtubules. 
E)  dense packing of ATP molecules. 
A)  dark color of myosin. 
B)  multiple nuclei per fiber. 
C)  regular arrangement of filaments. 
D)  dense array of microtubules. 
E)  dense packing of ATP molecules.

Question 16

A mutation in the gene encoding troponin has occurred in a mouse.What is a possible effect that this mutation could have on muscle activity?

Accepted Answer

A)  Signals from nerve impulses may be blocked from initiating an action potential in the muscle cell membrane. 
B)  An action potential may be prevented from traveling down the T tubules. 
C)  Calcium pumps in the sarcoplasmic reticulum may be blocked from releasing calcium into the sarcoplasm. 
D)  Increases in calcium concentration in the sarcoplasm may not lead to cross-bridge formation between actin and myosin. 
E)  Both c and d 
A)  Signals from nerve impulses may be blocked from initiating an action potential in the muscle cell membrane. 
B)  An action potential may be prevented from traveling down the T tubules. 
C)  Calcium pumps in the sarcoplasmic reticulum may be blocked from releasing calcium into the sarcoplasm. 
D)  Increases in calcium concentration in the sarcoplasm may not lead to cross-bridge formation between actin and myosin. 
E)  Both c and d

Question 17

A role of cartilage in the adult human skeleton is to

Accepted Answer

A)  bear heavy loads. 
B)  add flexibility. 
C)  be lightweight. 
D)  sustain vibrations. 
E)  grow rapidly. 
A)  bear heavy loads. 
B)  add flexibility. 
C)  be lightweight. 
D)  sustain vibrations. 
E)  grow rapidly.

Question 18

When animals die,muscles stiffen in rigor mortis because

Accepted Answer

A)  muscles cannot contract without ATP. 
B)  actin and myosin cannot bind without ATP. 
C)  ATP is required for synthesis of protein filaments. 
D)  ATP forms cross-bridges between filaments. 
E)  actin and myosin cannot separate without ATP. 
A)  muscles cannot contract without ATP. 
B)  actin and myosin cannot bind without ATP. 
C)  ATP is required for synthesis of protein filaments. 
D)  ATP forms cross-bridges between filaments. 
E)  actin and myosin cannot separate without ATP.

Question 19

In the first 15 minutes of a 10K run,the major energy source of the runner's leg muscles is

Accepted Answer

A)  preformed ATP. 
B)  glycolysis. 
C)  oxidative metabolism. 
D)  pyruvate and lactate. 
E)  the protein from his diet. 
A)  preformed ATP. 
B)  glycolysis. 
C)  oxidative metabolism. 
D)  pyruvate and lactate. 
E)  the protein from his diet.

Question 20

Which statement about the structure of skeletal muscle is true?

Accepted Answer

A)  The light bands of the sarcomere are the regions where actin and myosin filaments overlap. 
B)  When a muscle contracts,the A bands of the sarcomere lengthen. 
C)  The actin filaments are anchored by titin molecules to the Z lines. 
D)  When a muscle contracts,the H zone of the sarcomere shortens. 
E)  The sarcoplasm of the muscle cell is contained within the sarcoplasmic reticulum. 
A)  The light bands of the sarcomere are the regions where actin and myosin filaments overlap. 
B)  When a muscle contracts,the A bands of the sarcomere lengthen. 
C)  The actin filaments are anchored by titin molecules to the Z lines. 
D)  When a muscle contracts,the H zone of the sarcomere shortens. 
E)  The sarcoplasm of the muscle cell is contained within the sarcoplasmic reticulum.

Exam 33: Muscle and Movement

The role of Ca2+ in the control of muscle contraction is to

Cardiac muscle differs from both smooth and skeletal muscle in that

Exoskeletons of lobsters are composed of

Which structure is absent in cells of a fish electric organ?

To maintain high efficiency and greater power output with increasing wing beat frequencies,insect flight muscles have evolved

Which statement about skeletal systems is true?

Which is not one of the systems that supplies muscles with the ATP needed for contraction?

Refer to the diagram below.Which statement based on the diagram is true?

Shot-putters competing in track and field events need short,intense bursts of energy,but they tend to be quickly fatigued by the activity.An examination of the muscles used in this sport would show that they

The three systems by which muscles obtain ATP

An apodeme is

"_______" is the term used for the state of the adductor muscle of a mollusk as it maintains a contraction for an extended period of time.

A sarcomere is best described as a

What allows an earthworm to move through soil?

The striated appearance of skeletal muscle is due to the

A mutation in the gene encoding troponin has occurred in a mouse.What is a possible effect that this mutation could have on muscle activity?

A role of cartilage in the adult human skeleton is to

When animals die,muscles stiffen in rigor mortis because

In the first 15 minutes of a 10K run,the major energy source of the runner's leg muscles is

Which statement about the structure of skeletal muscle is true?

Introduction

The Chemistry and Energy of Life

Nucleic Acids, Proteins, and Enzymes

Cells: the Working Units of Life

Cell Membranes and Signaling

Pathways That Harvest and Store Chemical Energy

The Cell Cycle and Cell Division

Inheritance, Genes, and Chromosomes

DNA and Its Role in Heredity

From Dna to Protein: Gene Expression

Regulation of Gene Expression

Genomes

Biotechnology

Genes, Development, and Evolution

Processes of Evolution

Reconstructing and Using Phylogenies

Speciation

The History of Life on Earth

Bacteria, Archaea, and Viruses

The Origin and Diversification of Eukaryotes

The Evolution of Plants

The Evolution and Diversity of Fungi

Animal Origins and Diversity

The Plant Body

Plant Nutrition and Transport

Plant Growth and Development

Reproduction of Flowering Plants

Plants in the Environment

Fundamentals of Animal Function

Nutrition and Digestion

Breathing

Circulation

Neurons, Sense Organs, and Nervous Systems

Nervous and Endocrine Control

Water and Salts: Excretion

Animal Reproduction

Animal Development

Immunology: Animal Defense Systems

Animal Behavior

The Distribution of Earths Ecological Systems

Populations

Ecological and Evolutionary Consequences of Interactions Within and Among Species

Ecological Communities

The Global Ecosystem

Filters

The role of Ca²⁺ in the control of muscle contraction is to