040-444

040-444 practice questions, page 11 of 15, with answer review and explanations.

Question 51

When a motor unit is stimulated by a single nerve impulse, it responds by contracting one time and then relaxing. This is called a __________.

  1. Twitch.
  2. Summation.
  3. Tetanus.
  4. Summary.

Question 52

Which muscle protein contains many cross-bridges?

  1. Myofibril.
  2. Sarcomere.
  3. Troponin.
  4. Myosin.

Question 53

Cardiac muscle action potentials are longer in duration than those of skeletal muscle. The longer action potential does not allow the muscle to __________.

  1. Twitch.
  2. Undergo summation.
  3. Have tetanus.
  4. Summarize.

Question 54

Which of the following cardiovascular variables does NOT increase as a result of chronic exercise while performing a single bout of maximal exercise?

  1. Maximal HR.
  2. Maximal cardiac output.
  3. Maximal SV.
  4. Maximal oxygen consumption.

Question 55

Myocardial oxygen consumption is best estimated from __________.

  1. Maximal oxygen consumption.
  2. RPP.
  3. Cardiac output.
  4. HR.