Exam II Sample Question Answers

 

**Use these questions in combination with the previously posted questions for Quiz II.

 

1.         Which of the following is NOT TRUE for a lever where load is closer to the fulcrum than the applied effort?

 

A.        The lever may provide mechanical advantage

B.        The lever could be a first class lever

C.        The lever could be a third class lever

D.        A & B

E.         A, B & C

 

2.         In regard to the gross anatomy of muscle, which of the following is NOT TRUE?

 

A.        Perimysium is the more superficial than the epimysium

B.        Epimysium transfers force to tendons

C.        Endomysium surrounds individual muscle cells

D.        Each muscle cell is innervated by a single lower motor neuron

E.         A & B

 

3.         Of the following, may result when multiple alpha motor neurons are activated?

 

A.        Tetanus

B.        Temporal summation

C.        Recruitment

D.        Treppe

E.         All but B

 

4          Which of the following phases of a muscle twitch would be affected if electrical current moved more slowly through the t-tubule system?

 

A.        Latent phase

B.        Contraction phase

C.        Relaxation phase

D.        A & B

E.         A, B & C

 

5.         Which of the following membranes would be affected earliest during the contraction of a muscle?

 

A.        Perimysium

B.        Epimysium

C.        Endomysium

D.        Deep fascia

E.         A & B

 

6.         During muscle contraction, which of the following is TRUE for sarcomeres?

 

A.        Neighboring Z discs separate

B.        The A band decreases in size

C.        M lines of neighboring sarcomeres move closer together

D.        Z discs move closer to the M line

E.        C & D

 

7.         Which of the following types of muscle fibers have highly efficient myosin ATPases and utilize creatine phosphate?

 

A.        Slow oxidative fibers

B.        Fast oxidative fibers

C.        Fast glycolytic fibers

D.        A & B

E.         B & C

 

8.         Under non-pathological conditions, which of the following must occur when calcium is pumped back into the sarcoplasm?

 

A.        Acetycholine is inactivated

B.        Troponin must return to its “normal” shape

C.        Tropomyosin must return to its pre-contraction position

D.        Cross-bridges must break

E.         All but D

 

9.         Which of the following CANNOT be true when myosin is in the low-energy state?

 

A.        Myosin has high potential energy

B.        Myosin-ATPase is inactive

C.        ATP is attached to myosin

D.        Myosin is cross-bridged to actin

E.         A & C

 

10.       Regarding the contraction of skeletal muscle, which of the following is NOT TRUE?

 

A.        Current only flows in the t-tubules when ACh is bound to its receptors

B.        To end muscle contraction, calcium pumps be activated by ATP

C.        Bond energy from ATP is stored as a conformational change in the myosin head

D.        Cross bridging is not possible when tropomyosin covers actin binding sites

E.         C & D

 

11.       Of the following events listed below, which occurs immediately after ATP is attached to the myosin head?

 

A.        Ca2+ is released from the sacroplasmic reticulum

B.        Myosin goes into the high energy state

C.        Troponin undergoes a conformational change

D.        Myosin dissociates from the actin binding site

E.         Current flows through the T-tubule system

 

12.       During which of the following phases of a muscle twitch is the tension generated by the muscle changing?

 

A.        Latent phase

B.        Contraction phase

C.        Relaxation phase

D.        B & C

E.         A, B & C

 

13.       Which of the following is NOT TRUE for a lever where effort is applied at one end of the bar and the load is at point in between the fulcrum and effort?

 

A.        The lever may provide mechanical advantage

B.        Most muscles have this type of lever

C.        The lever is classified as a second class lever

D.        A & C

E.         B & C

 

14.       In regards to graded muscle responses, all of the following are true EXCEPT:

 

A.        As stimulus frequency increases a great number of motor units are activated

B.        Tetanic contraction results when stimulation occurs so quickly that Ca2+ levels cannot decrease

C.        Tension generated by individual fibers is proportionate to Ca2+ levels

D.        The amount of tension created by a muscle can increase even when the type and amount of stimulation does not change 

E.         A & D

 

15.       Drug X blocks acetylcholine receptors. Which is the most likely effect of Drug X?

 

A.        Acetylcholine cannot be released from the motor neuron

B.        Calcium cannot be pumped back into the sarcoplasmic reticulum

C.        Calcium will not be bound by troponin

D.        Myosin cannot bind ATP

E.         Tropomyosin cannot block myosin binding sites

 

16.       In regards to the gross anatomy of muscles, all of the following are true EXCEPT:

 

A.        Motor neurons usually form more than one neuromuscular junction

B.        The perimysium consists of areolar connective tissue   

C.        Fasciculi include multiple individual muscle fibers

D.        The perimysium is superficial to the endomysium

E.         A & C

 

17.       Assuming that ATP has just attached to the myosin head, which of the following must occur before contraction can occur?

 

A.        Myosin ATPase is active

B.        Acetylcholinesterase degrades acetylcholine

C.        Troponin binds calcium

D.        Calcium is released from the sarcolemma

E.        B & C

 

18.       The biceps brachii an example of which type of lever?

 

A.        First class

B.        Second class

C.        Third class

D.        Fourth class

E.         It does not function as a lever

 

19.       Which of the following CANNOT be true when active sites are covered?

 

A.        Ca2+ is bound to troponin

B.        Myosin-ATPase is active

C.        Actin is cross-bridged to myosin

D.        Myosin is in the high energy state

E.        A & C

 

20.       Of the following events listed below, which immediately precedes the release of the phosphorous functional group from the myosin head?

 

A.        ADP dissociates from the myosin head

B.        An action potential is generated in the motor neuron

C.        An action potential transfer through the T-tubule

D.        Myosin ATPase splits the ATP attached to the myosin head

E.        Actin and myosin cross-bridge