Question 1

A muscle is stimulated at a frequency that allows the muscle to relax completely between contractions. However, the amount of tension increases with each contraction. What is this called?

Accepted Answer

A)   tetanus
B)   treppe
C)   twitch
D)   recruitment
E)   summationF) C) and D)
G) A) and B)

Question 2

Which of the following is the property of skeletal muscle whereby an increase in the frequency of action potentials enhances the force developed by the muscle cell?

Accepted Answer

A)   internal tension
B)   external tension
C)   length -tension relationship
D)   summation
E)   force -velocity relationshipF) A) and C)
G) A) and B)

Question 3

Which of the following transmits action potentials to the interior of the muscle cell to trigger calcium release?

Accepted Answer

A)   motor end plate
B)   sarcoplasmic reticulum
C)   actin and myosin
D)   tendons
E)   sarcomeresF) A) and E)
G) C) and D)

Question 4

Which is the longest phase of a twitch?

Accepted Answer

A)   initial
B)   plateau
C)   contraction
D)   latent
E)   relaxationF) A) and B)
G) A) and C)

Question 5

The contractile portion of the thin filament is composed of what protein?

Accepted Answer

A)   myosin
B)   troponin
C)   actin
D)   tropomyosin
E)   titinF) C) and D)
G) B) and D)

Question 6

Which of the following appears as dark bands under the microscope?

Accepted Answer

A)   I band
B)   A band
C)   Z line
D)   M line
E)   H zoneF) B) and C)
G) A) and E)

Question 7

As the sarcomere length of skeletal muscle is reduced beyond the length where optimum force is developed,

Accepted Answer

A)   the thin filaments overlap one another with myosin bumping into the Z -line, thereby causing the force generated by crossbridges to be exerted on the sarcomere itself rather than transmitted to the ends of the muscle fiber.
B)   the amount of calcium released by the sarcoplasmic reticulum is reduced as length increases.
C)   the thin filaments are pulled away from one another, thereby reducing their ability to interact with myosin.
D)   the thick filaments are pulled away from one another, thereby reducing their ability to interact with actin.
E)   the thick filaments overlap one another, thereby reducing their ability to interact with actin.F) B) and C)
G) A) and D)

Question 8

What is the site where a muscle attaches to a stationary bone called?

Accepted Answer

A)   adductor
B)   flexor
C)   insertion
D)   abductor
E)   originF) A) and E)
G) All of the above

Question 9

Irrespective of an individual muscle cell's ability to regulate the amount of force developed by that cell, the force generated by a skeletal muscle is also controlled at the whole muscle level. Describe the mechanism whereby force of a whole muscle can be modified, including a discussion on motor units.

Accepted Answer

In addition to the ability of individual...

Question 10

Calcium for contraction comes entirely from the sarcoplasmic reticulum in which of the following?

Accepted Answer

A)   smooth muscle only (single -unit or multi -unit) 
B)   skeletal and smooth muscle only
C)   skeletal, smooth, and cardiac muscle
D)   skeletal muscle only
E)   smooth and cardiac muscle onlyF) A) and C)
G) All of the above

Question 11

Intercalated disks contain what type of special junctions?

Accepted Answer

A)   tight junctions only
B)   gap junctions only
C)   hemidesmosomes
D)   desmosomes
E)   both gap junctions and tight junctionsF) A) and B)
G) A) and C)

Question 12

In smooth muscle, calcium triggers contraction by binding to what protein?

Accepted Answer

A)   myosin light chain kinase
B)   calmodulin
C)   myosin light chain
D)   DHP receptors
E)   troponinF) B) and C)
G) A) and D)

Question 13

-What is the structure indicated by the number 5 in Figure 12.1 and what its functional significance?

Accepted Answer

A)   A band : length of myosin attached to an M line
B)   Z line : anchors the thin filaments together
C)   M line : where the tails of the myosin molecules are bound to one another
D)   sarcomere : the functional unit of muscle contraction whose length is changed as a muscle shortens and lengthens
E)   H zone : area of myosin not overlapped by actinF) B) and D)
G) None of the above

Question 14

The velocity at which a skeletal muscle contracts is (directly / inversely) related to load.

Accepted Answer

The answer of The velocity at which a skeletal muscle...

Question 15

The sequence of events that links the muscle's action potential to changes in skeletal muscle force development is called what?

Accepted Answer

A)   oxidative phosphorylation
B)   crossbridge cycling
C)   the sliding -filament model
D)   excitation -contraction coupling
E)   myoaction couplingF) None of the above
G) B) and D)

Question 16

Where are gap junctions commonly found?

Accepted Answer

A)   single -unit smooth muscle only
B)   multi -unit smooth muscle only
C)   cardiac muscle only
D)   both single -unit smooth muscle and cardiac muscle
E)   both single -unit and multi -unit smooth muscleF) A) and E)
G) A) and B)

Question 17

-What is the structure indicated by the number 2 in Figure 12.1 and what is its functional significance?

Accepted Answer

A)   H zone : area of myosin not overlapped by actin
B)   M line : where the tails of the myosin molecules are bound to one another
C)   Z line : anchors the thin filaments together
D)   sarcomere : the functional unit of muscle contraction whose length is changed as a muscle shortens and lengthens
E)   A band : length of myosin attached to an M lineF) A) and E)
G) A) and D)

Question 18

Calcium is stored in what region of skeletal muscle cells?

Accepted Answer

A)   tropomyosin
B)   actin
C)   transverse tubule
D)   sarcoplasmic reticulum
E)   troponinF) C) and D)
G) A) and C)

Question 19

Which of the following conditions will result in a skeletal muscle that produces a greater amount of force?

Accepted Answer

A)   more sarcomeres in series
B)   fewer sarcomeres in parallel
C)   fewer sarcomeres in series
D)   fewer myofibrils per muscle cell
E)   more sarcomeres in parallelF) C) and D)
G) D) and E)

Question 20

When an action potential is generated within a motor neuron,

Accepted Answer

A)   all of the muscle cells within the motor unit are stimulated to relax.
B)   the muscle cells of the motor unit will occasionally contract.
C)   only select muscle cells within the motor unit are stimulated to contract.
D)   every muscle cell of the motor unit is stimulated to contract.
E)   the muscle cells from a neighboring motor unit will contract.F) C) and E)
G) B) and C)

Exam 12: Muscle Physiology

-What is the structure indicated by the number 5 in Figure 12.1 and what its functional significance?

Correct Answer
verified

Which of the following conditions will result in a skeletal muscle that produces a greater amount of force?

Correct Answer
verified

-What is the structure indicated by the number 2 in Figure 12.1 and what is its functional significance?

Correct Answer
verified

Calcium for contraction comes entirely from the sarcoplasmic reticulum in which of the following?

Correct Answer
verified

The velocity at which a skeletal muscle contracts is (directly / inversely) related to load.

Correct Answer
verified

Intercalated disks contain what type of special junctions?

Correct Answer
verified

Which of the following appears as dark bands under the microscope?

Correct Answer
verified

A muscle is stimulated at a frequency that allows the muscle to relax completely between contractions. However, the amount of tension increases with each contraction. What is this called?

Correct Answer
verified

The sequence of events that links the muscle's action potential to changes in skeletal muscle force development is called what?

Correct Answer
verified

Where are gap junctions commonly found?

Correct Answer
verified

Calcium is stored in what region of skeletal muscle cells?

Correct Answer
verified

In smooth muscle, calcium triggers contraction by binding to what protein?

Correct Answer
verified

The contractile portion of the thin filament is composed of what protein?

Correct Answer
verified

When an action potential is generated within a motor neuron,

Correct Answer
verified

Which is the longest phase of a twitch?

Correct Answer
verified

Which of the following is the property of skeletal muscle whereby an increase in the frequency of action potentials enhances the force developed by the muscle cell?

Correct Answer
verified

As the sarcomere length of skeletal muscle is reduced beyond the length where optimum force is developed,

Correct Answer
verified

What is the site where a muscle attaches to a stationary bone called?

Correct Answer
verified

Correct Answer
verified
In addition to the ability of individual...
View Answer

Which of the following transmits action potentials to the interior of the muscle cell to trigger calcium release?

Correct Answer
verified

Exam 12: Muscle Physiology

-What is the structure indicated by the number 5 in Figure 12.1 and what its functional significance?

Correct AnswerverifiedShow Answer

Which of the following conditions will result in a skeletal muscle that produces a greater amount of force?

Correct AnswerverifiedShow Answer

-What is the structure indicated by the number 2 in Figure 12.1 and what is its functional significance?

Correct AnswerverifiedShow Answer

Calcium for contraction comes entirely from the sarcoplasmic reticulum in which of the following?

Correct AnswerverifiedShow Answer

The velocity at which a skeletal muscle contracts is (directly / inversely) related to load.

Correct AnswerverifiedShow Answer

Intercalated disks contain what type of special junctions?

Correct AnswerverifiedShow Answer

Which of the following appears as dark bands under the microscope?

Correct AnswerverifiedShow Answer

A muscle is stimulated at a frequency that allows the muscle to relax completely between contractions. However, the amount of tension increases with each contraction. What is this called?

Correct AnswerverifiedShow Answer

The sequence of events that links the muscle's action potential to changes in skeletal muscle force development is called what?

Correct AnswerverifiedShow Answer

Where are gap junctions commonly found?

Correct AnswerverifiedShow Answer

Calcium is stored in what region of skeletal muscle cells?

Correct AnswerverifiedShow Answer

In smooth muscle, calcium triggers contraction by binding to what protein?

Correct AnswerverifiedShow Answer

The contractile portion of the thin filament is composed of what protein?

Correct AnswerverifiedShow Answer

When an action potential is generated within a motor neuron,

Correct AnswerverifiedShow Answer

Which is the longest phase of a twitch?

Correct AnswerverifiedShow Answer

Which of the following is the property of skeletal muscle whereby an increase in the frequency of action potentials enhances the force developed by the muscle cell?

Correct AnswerverifiedShow Answer

As the sarcomere length of skeletal muscle is reduced beyond the length where optimum force is developed,

Correct AnswerverifiedShow Answer

What is the site where a muscle attaches to a stationary bone called?

Correct AnswerverifiedShow Answer

Correct AnswerverifiedIn addition to the ability of individual...View AnswerShow Answer

Which of the following transmits action potentials to the interior of the muscle cell to trigger calcium release?

Correct AnswerverifiedShow Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
In addition to the ability of individual...
View Answer

Correct Answer
verified