Question

6. During relaxation, calcium is transported into the sarcoplasmic reticulum by which of the following?

Na+/Ca++ antiport

Calcium ion ATPase Pump

Simple diffusion through Calcium ion channels

7 Which of the following has to occur in order to release the myosin head from actin at the end of the rigor state

A molecule of ATP must split

Calcium ions must be removed from the troponin-tropomyosin comples

ATP must bond to the myosin head, releasing the crossbridge

8. Which of the following describes the relationship between the type of metabolism used by a skeletal muscle fiber and its resistance to fatigue?

Muscle fibers with a high oxidative capacity have a high resistance to fatigue

Muscle fibers that have a high glycolytic ability do not fatigue

Muscle fibers with a low oxidative capacity are resistant to fatigue

9. What can you conclude about postural muscles?

These muscles contain fast oxidative muscle fibers that have a low resistance to fatigue

These muscles contain fast twtich muscle fibers that can correct posture changes rapidly

These muscles contain slow twtich muscles can sustain contraction while resisting fatigue

10 How to the type of muscle fibers change as the level of exercise intensity increases between an average couch potato, an average active person, a middle distance runner, a marathon runner and an extreme endurance athlete?

The percentage of slow twitch Type I fibers increases

The percentage of Fast twitch II X fibers increases

The percentage of fast twitch Type IIA fibers increases

Answer 1

6. Calcium ion ATPase Pump

Explanation:  Calcium ion ATPase Pump pumps the calcium actively back into sarcoplasmic reticulum.

7. ATP must bond to the myosin head, releasing the crossbridge

Explanation: myosin head first attaches to actin together with the products of ATP hydrolysis, performs a power stroke associated with release of hydrolysis products, and detaches from actin upon binding with new ATP.

8. Muscle fibers with a high oxidative capacity have a high resistance to fatigue

9. These muscles contain slow twtich muscles can sustain contraction while resisting fatigue

10. The percentage of slow twitch Type I fibers increases