B) The myosin heads pull the thin filaments toward the M line. A) The myosin heads bind to actin. 2. Which of the following does NOT happen during a muscle contraction? A) The myosin heads bind to actin. B) The myosin heads pull the thin filaments toward the M line. C) The sarcomere shortens. D) The myofiber and the muscle itself shorten. E) The thick and thin filaments shorten. Use the following to answer questions 3-5. Choose the answer that best matches the description or term. A) contractility B) elasticity C) electrical excitability D) extensibility E) thermogenic 3. property allowing muscle tissue to return to its original shape 4. property allowing muscle to shorten forcefully when stimulated by an action potential 5. function of muscle; heat generation 6. An instructor raises his eyebrows because he is very surprised by a student”s comment in class. Which of the following muscles is involved in his surprised expression?