BIOS-252: | BIOS 252 ANATOMY & PHYSIOLOGY II WITH LAB PRACTICE TEST 49 WITH CORRECT MARKING SCHEME

Which of the following is a recognized function of skeletal muscle? 1) A) guard body entrances and exits B) maintain posture C) maintain body temperature D) produce movement E) all of the above E Nerves and blood vessels that service the muscle fibers are located in the connective tissues of the A) myofibrils. B) sarcolemma. C) endomysium. D) sarcomere. E) perimysium. E Which of the following best describes the term sarcoplasmic reticulum? A) largely made of myosin molecules B) storage and release site for calcium ions C) thin filaments are anchored here D) protein that accounts for elasticity of resting muscle E) repeating unit of striated myofibrils B Interactions between actin and myosin filaments of the sarcomere are responsible for A) the conduction of neural stimulation to the muscle fiber. B) muscle fatigue. C) the striped appearance of skeletal muscle. D) muscle contraction. E) muscle relaxation. D The region of the sarcomere that always contains thin filaments is the A) Z line. B) A band. C) H band. D) M line. E) I band. E At rest, active sites on the actin are blocked by A) calcium ions. B) troponin molecules. C) tropomyosin molecules. D) myosin molecules. E) ATP molecules. C Cross-bridges are portions of A) actin molecules. B) myosin molecules. C) tropomyosin molecules. D) troponin molecules. E) calcium ions. B When a skeletal muscle fiber contracts, A) the zones of overlap get larger. B) the H bands and I bands get smaller. C) the Z lines get closer together. D) the width of the A band remains constant. E) all of the above E