Question 1

A flexor is a skeletal muscle whose shortening moves attached bones

Accepted Answer

A)  away from one another. 
B)  towards one another. 
C)  medially 
D)  laterally. 
A)  away from one another. 
B)  towards one another. 
C)  medially 
D)  laterally. B

Question 2

The hydrolysis of ATP causes myosin to immediately

Accepted Answer

A)  swivel, moving the actin molecule. 
B)  release of ADP. 
C)  release from the actin. 
D)  rotate into a position (cocked) to bind to actin. 
E)  bind more tightly to the actin (rigor). 
A)  swivel, moving the actin molecule. 
B)  release of ADP. 
C)  release from the actin. 
D)  rotate into a position (cocked) to bind to actin. 
E)  bind more tightly to the actin (rigor). D

Question 3

The tension generated in a skeletal muscle fiber is directly proportional to the number of

Accepted Answer

A)  thick and thin filaments present. 
B)  nebulin and titin molecules present. 
C)  high energy crossbridges formed. 
D)  low energy crossbridges formed. 
E)  active sarcomeres. 
A)  thick and thin filaments present. 
B)  nebulin and titin molecules present. 
C)  high energy crossbridges formed. 
D)  low energy crossbridges formed. 
E)  active sarcomeres. C

Question 4

Each myosin head has a binding site for

Accepted Answer

A)  calcium only. 
B)  actin only. 
C)  ATP only. 
D)  calcium and ATP. 
E)  actin and ATP. 
A)  calcium only. 
B)  actin only. 
C)  ATP only. 
D)  calcium and ATP. 
E)  actin and ATP.

Question 5

Describe the muscle condition called tetanus.Is this a normal or a pathological event? If it is normal,what is the function? If it is pathological,what is the cause? The bacterium Clostridium tetani causes a disease called tetanus or lockjaw; you may have been vaccinated against tetanus,especially if you ever had hospital treatment for a skin wound.Speculate on whether or not the name of this disease is related to the muscle condition and why the disease can be fatal.

Accepted Answer

Tetanus is a state of maintained contrac

Question 6

What are the three types of muscle tissues in the human body? What are the two common functions of muscles?

Accepted Answer

Three types of tissues are ske

Question 7

________ is composed of multiple globular molecules polymerized to form long chains or filaments.

Accepted Answer

A)  Actin 
B)  Tropomyosin 
C)  Troponin 
D)  Myosin 
E)  Titin 
A)  Actin 
B)  Tropomyosin 
C)  Troponin 
D)  Myosin 
E)  Titin

Question 8

Which of the following is NOT a correct comparison of cardiac myocytes to other muscle cell types?

Accepted Answer

A)  Like smooth muscle cells, some cardiac myocytes have pacemaker potentials. 
B)  Like some smooth muscle cells, cardiac myocytes are electrically coupled. 
C)  Like skeletal muscle cells, actin and myosin are organized into sarcomeres. 
D)  Like skeletal muscle, contraction of cardiac muscle is under autonomic nervous control. 
E)  Like smooth muscle cells, cardiac muscle is under hormonal control. 
A)  Like smooth muscle cells, some cardiac myocytes have pacemaker potentials. 
B)  Like some smooth muscle cells, cardiac myocytes are electrically coupled. 
C)  Like skeletal muscle cells, actin and myosin are organized into sarcomeres. 
D)  Like skeletal muscle, contraction of cardiac muscle is under autonomic nervous control. 
E)  Like smooth muscle cells, cardiac muscle is under hormonal control.

Question 9

Asynchronous activation of motor units is important because it functions to ________.

Accepted Answer

The answer of Asynchronous activation of motor units is important...

Question 10

The function of transverse tubules is to

Accepted Answer

A)  store Ca2+ ions inside the muscle fiber. 
B)  rapidly conduct action potentials to the interior of the muscle fiber. 
C)  ensure a supply of glycogen throughout the muscle sarcoplasm. 
D)  conduct ATP molecules out of the mitochondria throughout the sarcoplasm. 
A)  store Ca2+ ions inside the muscle fiber. 
B)  rapidly conduct action potentials to the interior of the muscle fiber. 
C)  ensure a supply of glycogen throughout the muscle sarcoplasm. 
D)  conduct ATP molecules out of the mitochondria throughout the sarcoplasm.

Question 11

When comparing complete tetanus with unfused (incomplete)tetanus,which is true?

Accepted Answer

A)  Complete tetanus involves some relaxation between twitches. 
B)  Complete tetanus involves development of maximum tension. 
C)  Complete tetanus occurs at a lower frequency of stimulation than unfused tetanus. 
D)  Complete tetanus would occur when there is more time between twitch contractions. 
A)  Complete tetanus involves some relaxation between twitches. 
B)  Complete tetanus involves development of maximum tension. 
C)  Complete tetanus occurs at a lower frequency of stimulation than unfused tetanus. 
D)  Complete tetanus would occur when there is more time between twitch contractions.

Question 12

During heavy exercise,the ATP requirements of active muscle are likely to be met by metabolism of

Accepted Answer

A)  protein. 
B)  fatty acids. 
C)  carbohydrates. 
D)  nucleotides. 
A)  protein. 
B)  fatty acids. 
C)  carbohydrates. 
D)  nucleotides.

Question 13

Most of the time,the parallel thick and thin filaments of the myofibrils are connected by ________ that span the space between myosin and actin molecules.

Accepted Answer

A)  tropomyosin molecules 
B)  crossbridges 
C)  nebulin molecules 
D)  sarcomeres 
E)  calcium ions 
A)  tropomyosin molecules 
B)  crossbridges 
C)  nebulin molecules 
D)  sarcomeres 
E)  calcium ions

Question 14

In order for the bicep muscle to shorten,the force applied by the muscle must be ________ the load applied at the hand.

Accepted Answer

A)  greater than 
B)  less than 
C)  equal to 
A)  greater than 
B)  less than 
C)  equal to

Question 15

The interaction between Ca2+ and calmodulin in smooth muscle cells has been described as a second messenger system.Develop an argument to support this position,using another second messenger system you have studied for comparison.

Accepted Answer

Ca²⁺ forms a complex with calmodulin.This

Question 16

In order for high force crossbridges to form in contracting skeletal muscle,calcium must

Accepted Answer

A)  bind to calmodulin to phosphorylate the myosin. 
B)  phosphorylate the tropomyosin which moves it. 
C)  phosphorylate the troponin to move the tropomyosin. 
D)  bind to tropomyosin which moves the troponin. 
E)  bind to troponin which moves the tropomyosin. 
A)  bind to calmodulin to phosphorylate the myosin. 
B)  phosphorylate the tropomyosin which moves it. 
C)  phosphorylate the troponin to move the tropomyosin. 
D)  bind to tropomyosin which moves the troponin. 
E)  bind to troponin which moves the tropomyosin.

Question 17

For antagonistic muscle groups to move a limb,flexor contraction occurs coincident with

Accepted Answer

A)  contraction of the extensor. 
B)  relaxation of the extensor. 
C)  no changes in the extensor. 
D)  contraction of the tendon. 
A)  contraction of the extensor. 
B)  relaxation of the extensor. 
C)  no changes in the extensor. 
D)  contraction of the tendon.

Question 18

The factor(s)that determine the duration of a twitch in various types of fibers is the speed of the

Accepted Answer

A)  removal of Ca2+ ions from the sarcoplasm only. 
B)  hydrolysis of ATP only. 
C)  movement of Na+ across their membranes only. 
D)  removal of Ca2+ ions from the sarcoplasm and hydrolysis of ATP. 
E)  removal of Ca2+ ions from the sarcoplasm and hydrolysis of ATP and movement of Na+ across their membranes. 
A)  removal of Ca2+ ions from the sarcoplasm only. 
B)  hydrolysis of ATP only. 
C)  movement of Na+ across their membranes only. 
D)  removal of Ca2+ ions from the sarcoplasm and hydrolysis of ATP. 
E)  removal of Ca2+ ions from the sarcoplasm and hydrolysis of ATP and movement of Na+ across their membranes.

Question 19

Match the structures with the accurate description.
-a single muscle cell

Accepted Answer

A) muscle fiber 
B) fascicle 
C) sarcolemma 
D) myofibril 
E) t-tubules 
A) muscle fiber 
B) fascicle 
C) sarcolemma 
D) myofibril 
E) t-tubules

Question 20

The gap junctions in cardiac muscle are part of specialized cell junctions that are localized to the ________.

Accepted Answer

The answer of The gap junctions in cardiac muscle are...

Exam 12: Muscles

A flexor is a skeletal muscle whose shortening moves attached bones

The hydrolysis of ATP causes myosin to immediately

The tension generated in a skeletal muscle fiber is directly proportional to the number of

Each myosin head has a binding site for

What are the three types of muscle tissues in the human body? What are the two common functions of muscles?

________ is composed of multiple globular molecules polymerized to form long chains or filaments.

Which of the following is NOT a correct comparison of cardiac myocytes to other muscle cell types?

Asynchronous activation of motor units is important because it functions to ________.

The function of transverse tubules is to

When comparing complete tetanus with unfused (incomplete)tetanus,which is true?

During heavy exercise,the ATP requirements of active muscle are likely to be met by metabolism of

Most of the time,the parallel thick and thin filaments of the myofibrils are connected by ________ that span the space between myosin and actin molecules.

In order for the bicep muscle to shorten,the force applied by the muscle must be ________ the load applied at the hand.

The interaction between Ca2+ and calmodulin in smooth muscle cells has been described as a second messenger system.Develop an argument to support this position,using another second messenger system you have studied for comparison.

In order for high force crossbridges to form in contracting skeletal muscle,calcium must

For antagonistic muscle groups to move a limb,flexor contraction occurs coincident with

The factor(s)that determine the duration of a twitch in various types of fibers is the speed of the

Match the structures with the accurate description. -a single muscle cell

The gap junctions in cardiac muscle are part of specialized cell junctions that are localized to the ________.

Introduction to Physiology

Molecular Interactions

Compartmentation: Cells and Tissues

Energy and Cellular Metabolism

Membrane Dynamics

Communication, Integration, and Homeostasis

Introduction to the Endocrine System

Neurons: Cellular and Network Properties

The Central Nervous System

Sensory Physiology

Efferent Division: Autonomic and Somatic Motor Control

Integrative Physiology I: Control of Body Movement

Cardiovascular Physiology

Blood Flow and the Control of Blood Pressure

Blood

Mechanics of Breathing

Gas Exchange and Transport

The Kidneys

Integrative Physiology II: Fluid and Electrolyte Balance

The Digestive System

Metabolism and Energy Balance

Endocrine Control of Growth and Metabolism

The Immune System

Integrative Physiology III: Exercise

Reproduction and Development

Filters

The interaction between Ca²⁺ and calmodulin in smooth muscle cells has been described as a second messenger system.Develop an argument to support this position,using another second messenger system you have studied for comparison.