Practice Chapter 6 Multiple Choice Identify the choice that best completes the statement or answers the question. 1. Voluntary muscle tissue is; a. smooth muscle b. skeletal muscle c. dense regular d. cardiac muscle e. dense irregular 2. Endomysium covers: a. fascicles of muscle cells b. an entire muscle c. an individual muscle cell d. myofibrils e. smooth muscle only 3. The type of muscle tissue pictured in Figure 6.3 is: a. skeletal muscle b. voluntary c. striated d. found only in the heart e. smooth muscle Figure 6.3 4. A sarcomere is: a. the nonfunctional unit of skeletal muscle b. the contractile unit between two Z discs c. the area between two intercalated discs d. the wavy lines on the cell, as seen in a microscope e. a compartment in a myofilament
5. Which one of the following is composed of myosin protein: a. thick filaments b. thin filaments c. all myofilaments d. Z discs e. light bands 6. Place these structures of the skeletal muscle in order from largest to smallest: 1. fascicle 2. myofilament 3. muscle fiber (cell) 4. myofibril 5. sarcomere a. 1, 3, 4, 5, 2 b. 1, 4, 3, 2, 5 c. 2, 5, 4, 3, 1 d. 3, 1, 2, 4, 5 e. 3, 2, 5, 4, 1 7. The light and dark banding pattern send in striated muscle, like skeletal muscle, originate from: a. presence of H zones and Z discs b. layers of thick and thin filaments c. alternating light and dark bands d. repetitive Z discs e. organization of M lines, H zones, and Z discs 8. Why are calcium ions necessary for skeletal muscle contraction: a. calcium increases the action potential transmitted along the sarcolemma b. calcium releases the inhibition on Z discs c. calcium triggers the binding of myosin to actin d. calcium causes ATP binding to actin e. calcium binds to regulatory proteins on the myosin filaments, changing both their shape and their position on the thick filaments 9. Acetylcholine is: a. an ion pump on the postsynaptic membrane b. a source of energy for muscle contraction c. a component of thick myofilaments d. an oxygen-binding protein e. a neurotransmitter that stimulates skeletal muscle 10. The gap between the axon terminal of a motor neuron and the sarcolemma of a skeletal muscle cell is called the: a. motor unit b. sarcomere c. neuromuscular junction d. synaptic cleft e. cross bridge
11. Neurotransmitters are released upon stimulation from a nerve impulse by the: a. myofibrils b. motor unit c. thick filaments d. axon terminals of the motor neuron e. sarcolemma of the muscle cell 12. An elaborate and specialized network of membranes in skeletal muscle cells that function in calcium storage is the: a. sarcolemma b. mitochondria c. intermediate filament network d. myofibrillar network e. sarcoplasmic reticulum 13. Anaerobic glycolysis occurs without: a. ATP b. oxygen c. lactic acid d. carbon dioxide e. glucose 14. Which of these pathways is the fastest way to regenerate ATP during muscle activity: a. direct phosphorylation of ADP by creatine phosphate b. aerobic respiration c. anaerobic glycolysis and lactic acid formation d. oxidative phosphorylation e. both aerobic respiration and anaerobic glycolysis 15. Which of the following muscles closes the jaw: a. buccinator b. zygomaticus c. frontalis d. sternocleidomastoid e. both masseter and temporalis 16. A muscle located on the ventral (anterior) side of the body is the: a. pectoralis major b. occipitalis c. gastrocnemius d. gluteus medius e. latissimus dorsi
17. A nursing infant develops a powerful sucking muscle that adults also use for whistling or blowing a trumpet called the: a. platysma b. masseter c. zygomaticus d. buccinator e. temporalis 18. What is the main function of the quadriceps femoris group: a. arm flexion b. hand supination c. thigh abduction d. knee extension e. foot inversion 19. Which one of the following is the action of the orbicularis oris: a. closes, purses, and protrudes the lips b. pulls the lower lip down and back c. draws the eyebrows together d. allows blinking, squinting, and various other protective mechanisms for the eye e. closes the jaw 20. Paralysis of which of the following would make an individual unable to flex the hip: a. biceps femoris b. gastrocnemius c. tibialis anterior d. sartorius e. iliopsoas 21. Which one of the following muscles is involved in abduction of the arm at the shoulder joint: a. deltoid b. biceps brachii c. triceps brachii d. latissimus dorsi e. pectoralis major 22. What is the origin of the deltoid muscle: a. proximal radius b. proximal humerus c. distal humerus d. olecranon process of ulna e. scapular spine and clavicle
23. While doing "jumping jacks" during an exercise class, your arms and legs move laterally away from the midline of your body. This motion is called: a. extension b. flexion c. abduction d. adduction e. circumduction 24. Which congenital muscle disease results from the degeneration and atrophy of muscles: a. muscular dystrophy b. myasthenia gravis c. multiple sclerosis d. spina bifida e. scoliosis 25. Which one of the following is NOT a criteria generally used in naming muscles: a. relative size of the muscle b. number of origins of the muscle c. shape of the muscle d. method of attachment of the muscle to bone e. action of the muscle True/False Indicate whether the statement is true or false. 26. All types of muscle have endomysium covering individual muscle cells. 27. Smooth muscles activity generates heat to help maintain body temperature. 28. The sarcoplasmic reticulum wraps like a sleeve around the myofibril and stores and releases calcium. 29. The neurotransmitter used by the nervous system to activate skeletal muscle cells is acetylcholine. 30. Thick filaments are made of a protein called actin. 31. Oxygen debt promotes lactic acid accumulation on muscles from anaerobic cellular respiration. 32. A sustained partial contraction of skeletal muscle is called muscle tone. 33. An aponeurosis is a ropelike piece of muscle fascia that forms indirect connections to muscles of the leg. 34. The hamstring group inserts into the distal tibia. 35. Supination and pronation refer to up and down movements of the foot at the ankle.
Essay 36. Compare skeletal, smooth, and cardiac muscles as to their body location, microscopic anatomy, regulation of contraction, speed of contraction, and rhythmicity. 37. Discuss the importance of calcium in skeletal muscle contraction.
Practice Chapter 6 Answer Section MULTIPLE CHOICE 1. ANS: B PTS: 1 DIF: 2 REF: Page 182 Page 183 2. ANS: C PTS: 1 DIF: 2 REF: Page 183 3. ANS: E PTS: 1 DIF: 2 REF: Page 182 4. ANS: B PTS: 1 DIF: 2 REF: Page 187 5. ANS: A PTS: 1 DIF: 2 REF: Page 187 6. ANS: A PTS: 1 DIF: 3 REF: Page 183 Page 187 7. ANS: C PTS: 1 DIF: 3 REF: Page 187 8. ANS: C PTS: 1 DIF: 2 REF: Page 191 9. ANS: E PTS: 1 DIF: 1 REF: Page 188 10. ANS: D PTS: 1 DIF: 2 REF: Page 188 11. ANS: D PTS: 1 DIF: 2 REF: Page 188 12. ANS: E PTS: 1 DIF: 1 REF: Page 187 13. ANS: B PTS: 1 DIF: 3 REF: Page 194 14. ANS: A PTS: 1 DIF: 3 REF: Page 194 15. ANS: E PTS: 1 DIF: 2 REF: Page 206 16. ANS: A PTS: 1 DIF: 1 REF: Page 207 17. ANS: D PTS: 1 DIF: 1 REF: Page 206 18. ANS: D PTS: 1 DIF: 2 REF: Page 213 19. ANS: A PTS: 1 DIF: 1 REF: Page 205 20. ANS: E PTS: 1 DIF: 2 REF: Page 211 Page 213 21. ANS: A PTS: 1 DIF: 2 REF: Page 209 22. ANS: E PTS: 1 DIF: 3 REF: Page 209 23. ANS: C PTS: 1 DIF: 1 REF: Page 200 24. ANS: A PTS: 1 DIF: 3 REF: Page 215 25. ANS: D PTS: 1 DIF: 2 REF: Page 202 TRUE/FALSE 26. ANS: T PTS: 1 DIF: 2 REF: Page 182-184 27. ANS: F PTS: 1 DIF: 1 REF: Page 185 28. ANS: T PTS: 1 DIF: 1 REF: Page 187 29. ANS: T PTS: 1 DIF: 1 REF: Page 188 30. ANS: F PTS: 1 DIF: 1 REF: Page 187 31. ANS: T PTS: 1 DIF: 2 REF: Page 194 32. ANS: T PTS: 1 DIF: 1 REF: Page 195 33. ANS: F PTS: 1 DIF: 1 REF: Page 183 34. ANS: F PTS: 1 DIF: 2 REF: Page 213 35. ANS: F PTS: 1 DIF: 2 REF: Page 200
ESSAY 36. ANS: Body location skeletal muscle is attached to bones or to skin (some facial muscles); cardiac muscle is located in the walls of the heart; smooth muscle is found in the walls of hollow visceral organs (other than the heart). Microscopic anatomy skeletal muscle consists of very long, cylindrical, multinucleated cells with very obvious striations; cardiac muscle consists of branching chains of cells that are uninucleated and possess striations; smooth muscle consists of single fusiform uninucleated cells that lack striations. Regulation of contraction skeletal muscle is voluntary via nervous system controls, but this normal voluntary control can be overridden by involuntary reflex arcs (as explained in later chapters); cardiac muscle is involuntary via the heart pacemaker, nervous system controls, and hormones; smooth muscle is involuntary via nervous system controls, hormones, other chemicals, and stretching. Speed of contraction skeletal muscle is slow to fast; cardiac muscle is slow; smooth muscle is the slowest. Rhythmicity skeletal muscle is arrhythmic; cardiac muscle is rhythmic; smooth muscle is sometimes rhythmic. PTS: 1 DIF: 2 REF: Page 182-184 37. ANS: Calcium is necessary for myosin heads to attach to binding sites on actin filaments. As the action potential travels into the muscle cell, it stimulates the sarcoplasmic reticulum surrounding each myofibril to release its stored calcium into the sarcoplasm. The calcium triggers the binding of myosin heads to actin filaments and the initiation of the sliding of filaments. PTS: 1 DIF: 2 REF: Page 188-191