The is the basic unit of contraction. a. osteoblast c. muscle fiber b. sarcomere d. myosin filament

The condition rigor mortis develops several hours after death, it is characterized by muscular rigidity, it happens because   a. Because of a lack of ATP   b. Because actin can’t detach from the myosin head   c. At death, calcium ions leak out of the SR and trigger a muscle contraction   d. a, b and c   e. Only a   f. Only c

Put the following items in order of decreasing size: 63. Sección Largest 64. 65. 66. 67. Smallest A. Calcium В. Мyofibril C. Myofilament D. Sarcomere E. Tropomyosin

Which of the following statements relating to the developmental aspects of muscles is false? a. All muscle tissue types arise from myoblasts b. Skeletal muscles become amitotic while smooth muscles regenerate throughout life c. Sarcopenia begins by age 30 and is irreversible d. Body strength per unit muscle mass is the same in both sexes  e. none of the above   Which of the following structures is located in the head region of the thick filament myosin? a. actin binding site b. ATP binding site c. ATPase enzyme d. all of the above e. none of the above