Practice Questions on the Muscular System
Page 2

  1. The smallest contractile unit in a skeletal muscle fiber is a ____________.
  2. The major regulatory proteins in muscle tissue are:
    1. Myosin and tropomyosin
    2. Myosin and actin
    3. Actin and rhodopsin
    4. Troponin and tropomyosin
    5. Calmodulin and keratin

  3. Which of the following actions is caused by skeletal muscle?
    1. Vasoconstriction
    2. Vasodilation
    3. Pupillary dilation
    4. Eye movements
    5. Heartbeat

  4. Which of the following does NOT occur in a muscle during a contraction?
    1. Thick and thin filaments interact
    2. Muscle fibers stretch
    3. Thick and thin filaments "slide" past one another
    4. Muscle fibers shorten

  5. This process aids in skeletal muscle relaxation after contraction.
    1. Ca2+ is released from intracellular storage sites
    2. Motor neurons send electrical signals to muscle fibers
    3. Acetylcholinesterase synthesizes acetylcholine
    4. Troponin binds Ca2+
    5. None of the above

  6. The stiffness of muscle tissue in rigor mortis partially results from excessive:
    1. ACh activity on muscle
    2. Ca2+ release in muscle
    3. Lactic acid build up
    4. Fiber contraction
    5. All of the above

  7. A single motor neuron may innervate as few as 3 fibers in the muscles of the:
    1. Brachial region
    2. Eye
    3. Anterior cervical region
    4. Gingiva
    5. Calf

  8. When an AP reaches the presynaptic terminal of the motor neuron:
    1. Calcium is released into the muscle fiber
    2. ACh is released into the synaptic cleft
    3. AChase is released into the synpatic cleft
    4. Calcium is released from the motor neuron nucleus

  9. Lack of AChase in the synaptic cleft would result in:
    1. Excessive, continuous stimulation of the muscle fiber
    2. Relaxation of the muscle fiber
    3. Increased Na+ synthesis by the muscle fiber
    4. Inability of the motor neuron to conduct further action potentials

  10. The toxin curare blocks the ACh receptors on muscle tissue. This would result in:
    1. Increased stimulation of the muscle fiber
    2. Increased contractile strength of the muscle fiber
    3. Nonconsecutive eccentric contractions
    4. Excessive contractions
    5. Inability of muscle to respond to the motor neuron stimulus

  11. Jogging, swimming, and aerobics all have this effect on skeletal muscle tissue.
    1. Increased # of mitochondria per muscle cell
    2. Increased # of muscle fibers
    3. Increased # of motor units
    4. Decreased # of skeletal muscle fibers
    5. None of the above

  12. Muscular dystrophy is a congenital disorder characterized by:
    1. Skeletal muscle degeneration
    2. Excessive convulsions
    3. Compulsive muscle spasms
    4. Smooth muscle hypertrophy

  13. Anabolic steroids have all these effects EXCEPT:
    1. Muscle protein synthesis
    2. Increased muscular strength
    3. Increased number of muscles in the body
    4. Possible liver cancer
    5. Possible testicular atrophy

  14. Which of the following statements regarding aging and the muscular system is true?
    1. Aging is associated with decreased myoglobin production
    2. Effects of aging can be nearly reversed
    3. The satellite cells will differentiate into motor neurons when an individual is advanced in age
    4. Youngsters have more adipocytes in muscle tissue than the elderly

    In the following 4 questions, choose whether the characteristic applies to single unit smooth muscle and/or to multi-unit smooth muscle.

  15. Gap Junctions
  16. Pacemaker potential
  17. Fiber recruitment
  18. ANS innervation

    Go to page: 1 2
    Go back to my Main A&P Page
    Go to the index of question topics