Question 1

Impressive was a champion Quarter Horse stallion with a magnificent muscular physique,a trait that he passed on to dozens of offspring.However,many of Impressive's offspring developed periodic muscular twitching that sometimes left the horses temporarily unable to move.Some horses even died.As it turns out,Impressive's award-winning physique was due to a mutation in a single,protein-encoding gene,resulting in hyperexcitable muscle (which contracts even in the absence of a stimulus from its motor neuron) .Which is NOT a plausible explanation for the identity of the abnormal muscle protein in Impressive and his offspring?

Accepted Answer

A)  acetylcholine receptors that function in the absence of acetylcholine
B)  leaky Na+ channels
C)  overactive Ca2+ pumps in the membrane of the sarcoplasmic reticulum
D)  tropomyosin that is unable to bind to actin
E)  over-active troponin moleculesF) All of the above
G) A) and C)

Question 2

Which of the following regarding the Haversian System is false?

Accepted Answer

A)  It keeps osteocytes alive.
B)  Haversian canals may contain nerve fibers.
C)  Haversian canals run parallel to the length of long bone.
D)  Haversian canals are created by osteoclasts that tunnel through the bone matrix.E) B) and D)
F) A) and B)

Question 3

What is the association between tropomyosin and troponin molecules in resting striated muscle fibers?

Accepted Answer

A)  Tropomyosin holds the troponin in place on the myosin.
B)  Troponin holds the tropomyosin in place on the myosin.
C)  Tropomyosin holds the troponin in place on the actin.
D)  Troponin holds the tropomyosin in place on the actin.
E)  There is no known association.F) None of the above
G) C) and E) D

Question 4

In order for an earthworm to lengthen several contiguous segments of its body,it must

Accepted Answer

A)  contract its circular muscles,which pulls up the chaetae and moves the body fluid parallel to the long axis of the worm.
B)  contract its longitudinal muscles,which pulls up the chaetae and moves the body fluid perpendicular to the long axis of the worm.
C)  contract its circular muscles,which extends the chaetae into the surrounding soil and moves the body fluid parallel to the long axis of the worm.
D)  contract its longitudinal muscles,which extends the chaetae into the surrounding soil and moves the body fluid parallel to the long axis of the worm.
E)  contract its circular muscles,which extends the chaetae into the surrounding soil and moves the body fluid perpendicular to the long axis of the worm.F) C) and D)
G) B) and D)

Question 5

The myofibrils consist of both thin filaments made of actin and thick filaments composed of

Accepted Answer

A)  myosin.
B)  troponin.
C)  chitin.
D)  tropomyosin.
E)  acetylcholine.F) B) and E)
G) A) and B)

Question 6

The human skeleton is a typical vertebrate

Accepted Answer

A)  endoskeleton.
B)  exoskeleton.
C)  hydrostatic skeleton.
D)  axial skeleton only.
E)  appendicular skeleton only.F) A) and D)
G) B) and C)

Question 7

Impulses conducted along the transverse tubules of the muscle fiber stimulate

Accepted Answer

A)  the release of ATP.
B)  the binding of actin to the Z lines.
C)  tropomyosin and troponin binding.
D)  the release of calcium ions.
E)  the release of acetylcholine.F) B) and C)
G) A) and B)

Question 8

As the Baby Boomer generation ages,more and more joint replacement surgeries take place each year.Hip replacement surgery is the gold standard of all joint replacement surgeries,with many patients able to walk just a few hours after surgery and return home the very next day.In contrast,knee replacement surgery usually requires hospital stays of several days,followed by weeks to months of physical therapy.What best explains why the recovery after hip replacement surgery is so much faster than after knee replacement surgery?

Accepted Answer

A)  The hip joint is more superficial and more accessible to surgeons than the knee joint.
B)  The knee joint is stabilized by many more structures (many of which have to be cut) than the hip joint.
C)  The hip only moves in one direction,and recovery of one motion is easier than recovering movement in many directions.
D)  The upper end of the thigh bone has less overall surface contact with the hip bone than its lower end has in the knee with bones of the lower leg.
E)  The knee is a type of combination joint,which are difficult to replace.F) C) and E)
G) B) and E)

Question 9

The use-dependent decrease in the ability of a muscle to generate force is called ________.

Accepted Answer

A)  tetanus
B)  aerobic fitness
C)  fatigue
D)  enduranceE) A) and D)
F) B) and C)

Question 10

According to the figure,which one represents the muscle in an optimal condition for a strong contraction?

Accepted Answer

A)  A
B)  B
C)  C
D)  DE) None of the above
F) B) and D)

Question 11

In bone,crystals of calcium phosphate impregnate the extracellular matrix containing fibers of

Accepted Answer

A)  actin.
B)  chitin.
C)  collagen.
D)  myosin.
E)  troponin.F) A) and E)
G) C) and D)

Question 12

If you rub the scaled skin of a shark,it feels rough if you move your hand from tail to head but smooth if you move from head to tail.What is a major advantage of the scales being oriented this way?

Accepted Answer

A)  to counteract friction as the shark swims through the water
B)  to keep the shark afloat in the water
C)  to better protect the shark from predators
D)  to better prevent water loss from the body tissues
E)  to enable the shark to orient itself in space and detect preyF) B) and D)
G) A) and E)

Question 13

The movement of actin and myosin fibers in a muscle contraction contains all of the following steps EXCEPT

Accepted Answer

A)  the myosin head attaches to the actin filament.
B)  myosin rolls up from one end,forming a ball.
C)  the myosin filament advances relative to the actin filament.
D)  the globular myosin head detaches from the actin filament.
E)  the myosin head returns to its original conformation.F) C) and D)
G) B) and E)

Question 14

Sustained contraction is called

Accepted Answer

A)  twitching.
B)  summation.
C)  tetanus.
D)  recruitment.
E)  isometric binding.F) A) and C)
G) B) and E)

Question 15

Which of the following is/are required with actin and myosin in order to initiate muscle contraction?

Accepted Answer

A)  ATP
B)  calcium
C)  phosphate
D)  calcium and ATP
E)  calcium and phosphateF) A) and D)
G) C) and D) D

Question 16

Utilizing more motor units for stronger muscle contractions is called

Accepted Answer

A)  fast-twitching.
B)  fatigue.
C)  aerobic capacity.
D)  recruitment.
E)  insertion.F) A) and B)
G) All of the above

Question 17

The figure below represents a joint in the hind leg of a grasshopper.The exoskeleton of the leg is indicated by the two pairs of parallel black lines.A muscle that moves this leg is fixed to the skeleton at the end marked with a blue star.When the muscle contracts,it will pull on the tendon at its opposite end.Which configuration shows the most likely arrangement of the exoskeleton and a muscle that increases the flexion of this leg?

Accepted Answer

A)  A
B)  B
C)  C
D)  DE) B) and D)
F) B) and C)

Question 18

You have just read an advertisement for a new drug that claims people who take it can get muscular bodies without spending months lifting weights in the gym.The drug stimulates muscle growth in the same way that weight lifting does,which is to

Accepted Answer

A)  stimulate growth in the size of existing muscle fibers.
B)  stimulate existing muscle fibers to divide.
C)  stimulate existing muscle fibers to fuse with one another.
D)  turn surrounding connective tissue into muscle tissue.
E)  stimulate an increase in the proportion of slow-twitch muscle fibers.F) D) and E)
G) A) and B) A

Question 19

Insects such as mosquitoes and beetles can beat their wings at tremendous speeds.This can be accomplished because

Accepted Answer

A)  their wing muscle contractions causes another set of muscles to stretch which in turn produces another contraction without waiting for the arrival of a nerve impulse.
B)  their wing muscle contractions cause another set of muscles to relax which in turn produces another wing movement.
C)  their wing muscle contractions are stimulated by the continuous nerve signal impulses which produce a continuous contraction of their wing muscles.
D)  their wing muscle contractions are capable of producing more ATP which allows these insects to have much faster and sustained wing movements.
E)  their wing muscle contractions produce nerve impulses which lead to more contraction of the wing muscles which in turn permits faster motion of the wings.F) C) and D)
G) B) and D)

Question 20

One adaptation to flight in birds is lighter bones,which lack

Accepted Answer

A)  calcium.
B)  collagen.
C)  bone marrow.
D)  the periosteum.
E)  medullary cavities.F) D) and E)
G) A) and C)

Exam 45: The Musculoskeletal System

Correct Answer
verified

Which of the following regarding the Haversian System is false?

Correct Answer
verified

What is the association between tropomyosin and troponin molecules in resting striated muscle fibers?

Correct Answer
verified
D

In order for an earthworm to lengthen several contiguous segments of its body,it must

Correct Answer
verified

The myofibrils consist of both thin filaments made of actin and thick filaments composed of

Correct Answer
verified

The human skeleton is a typical vertebrate

Correct Answer
verified

Impulses conducted along the transverse tubules of the muscle fiber stimulate

Correct Answer
verified

Correct Answer
verified

The use-dependent decrease in the ability of a muscle to generate force is called ________.

Correct Answer
verified

According to the figure,which one represents the muscle in an optimal condition for a strong contraction?

Correct Answer
verified

In bone,crystals of calcium phosphate impregnate the extracellular matrix containing fibers of

Correct Answer
verified

If you rub the scaled skin of a shark,it feels rough if you move your hand from tail to head but smooth if you move from head to tail.What is a major advantage of the scales being oriented this way?

Correct Answer
verified

The movement of actin and myosin fibers in a muscle contraction contains all of the following steps EXCEPT

Correct Answer
verified

Sustained contraction is called

Correct Answer
verified

Which of the following is/are required with actin and myosin in order to initiate muscle contraction?

Correct Answer
verified
D

Utilizing more motor units for stronger muscle contractions is called

Correct Answer
verified

Correct Answer
verified

You have just read an advertisement for a new drug that claims people who take it can get muscular bodies without spending months lifting weights in the gym.The drug stimulates muscle growth in the same way that weight lifting does,which is to

Correct Answer
verified
A

Insects such as mosquitoes and beetles can beat their wings at tremendous speeds.This can be accomplished because

Correct Answer
verified

One adaptation to flight in birds is lighter bones,which lack

Correct Answer
verified

Exam 45: The Musculoskeletal System

Correct AnswerverifiedShow Answer

Which of the following regarding the Haversian System is false?

Correct AnswerverifiedShow Answer

What is the association between tropomyosin and troponin molecules in resting striated muscle fibers?

Correct AnswerverifiedD

In order for an earthworm to lengthen several contiguous segments of its body,it must

Correct AnswerverifiedShow Answer

The myofibrils consist of both thin filaments made of actin and thick filaments composed of

Correct AnswerverifiedShow Answer

The human skeleton is a typical vertebrate

Correct AnswerverifiedShow Answer

Impulses conducted along the transverse tubules of the muscle fiber stimulate

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

The use-dependent decrease in the ability of a muscle to generate force is called ________.

Correct AnswerverifiedShow Answer

According to the figure,which one represents the muscle in an optimal condition for a strong contraction?

Correct AnswerverifiedShow Answer

In bone,crystals of calcium phosphate impregnate the extracellular matrix containing fibers of

Correct AnswerverifiedShow Answer

If you rub the scaled skin of a shark,it feels rough if you move your hand from tail to head but smooth if you move from head to tail.What is a major advantage of the scales being oriented this way?

Correct AnswerverifiedShow Answer

The movement of actin and myosin fibers in a muscle contraction contains all of the following steps EXCEPT

Correct AnswerverifiedShow Answer

Sustained contraction is called

Correct AnswerverifiedShow Answer

Which of the following is/are required with actin and myosin in order to initiate muscle contraction?

Correct AnswerverifiedD

Utilizing more motor units for stronger muscle contractions is called

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

You have just read an advertisement for a new drug that claims people who take it can get muscular bodies without spending months lifting weights in the gym.The drug stimulates muscle growth in the same way that weight lifting does,which is to

Correct AnswerverifiedA

Insects such as mosquitoes and beetles can beat their wings at tremendous speeds.This can be accomplished because

Correct AnswerverifiedShow Answer

One adaptation to flight in birds is lighter bones,which lack

Correct AnswerverifiedShow Answer

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D

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D

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A

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