Download 57. Which of the following changes occur in the sarcomere during

57. Which of the following changes occur in the sarcomere during skeletal muscle contraction?
1. The A band shortens.
3. The M line disappears
2. The I band shortens.
4. The A band remains the same
length.
A. 1 and 3
B. 2 and 4
C. 1, 2, and 3
D. All of the above
E. None of the above
58. Which of the following statements about smooth and skeletal muscle is true?
A. Smooth muscle cells are uninucleated, skeletal muscle cells are multinucleated.
B. The myofilaments in skeletal muscle are actin and myosin, and the myofilaments in
smooth muscle are titin and elastin.
C. Skeletal muscle is electrically excitable, smooth muscle does not respond to electrical
stimulation.
D. Smooth muscle is innervated, but skeletal muscle is not innervated.
E. More than one of the above answers is correct.
59. Postural muscles and the quadriceps femoris muscles consist of primarily __________________
fibers, and the extrinsic eye muscles are primarily ____________________ fibers.
A. Type I, Type II
B. Type II, Type I
C. Type I, Type IIb
D. Type IIb, Type I
E. Type IIa, Type IIb
60. An example of a skeletal muscle that works as a class III lever system is:
A. Biceps brachii
B. Gastrocnemius
C. Soleus
D. Splenius capitis
61. Which structure conducts an electric potential to the center of a myofiber?
A. Sarcoplasm
B. Sarcoplasmic reticulum
C. T-tubules
D. Sarcolemma
62. The connective tissue covering responsible for compartmentalizing muscles into groups (e.g.
anterior compartment of the thigh) is:
A. Endomysium
B. Perimysium
C. Epimysium
D. Deep fascia
E. Superficial fascia