Bio 201 Tissues and Skin 1 February 23, 2011 Biology 201-Worksheet on Muscle System (Answers are in your power point outlines-there is no key!) 1. Name and define 5 characteristics of the muscle system. 2. Identify the Latin or Greek roots for the following terms. Flesh Muscle 3. Name the 3 kinds of muscle. 4. Any change in oneʼs external or internal environments is called a(n): 5. Distinguish between a threshold and subthreshold stimulus. 6. Define Action Potential. 7. List 3 functions of muscle. 8. Write the equation for the breakdown and synthesis of ATP. 9. Fill in the missing information in the table below regarding a comparison among the 3 muscle types. Alternate Name Type of Control Striations Cell Shape Number of nuclei Nucleus Location Cell Length Location in Body Special Features SKELETAL CARDIAC SMOOTH 10. Which muscle type is cardiac muscle structurally most similar to? 11. What does anastomosing mean with regard to cardiac muscle? 12. What is an intercalated disc? 13. Order the following structures from largest to smallest: Myofibrils, Fascicles, Belly, Muscle fiber, Sarcomere, Myofilaments, Actin, Myosin. 14. Identify the macrostructures based on the information provided. a. A bundle of muscle cells; subdivisions of the belly. b. Muscle cell. c. Connective tissue enclosing each muscle cell. d. Enlarged central region of the muscle. e. Connective tissue enclosing each fascicle.
Bio 201 Tissues and Skin 2 February 23, 2011 f. Cord of connective tissue anchoring muscle to bone. g. Point of fixed position when the muscle contracts. h. Connective tissue enclosing entire belly. i. Point where tendon pulls on bone and causes movement. j. Structure that encloses and protects tendons. k. A broad flat tendon. 15. What is the function(s) of the mysium tissues that surround muscle? 16. What is tendinitis? 17. What causes muscle cells to have multiple nuclei? 18. Identify the parts of a muscle cell based on the information provided. a. Funnel-like infoldings of sarcolemma that penetrate deep into cellʼs interior. b. The endoplasmic reticulum of a muscle cell. c. The plasma membrane of a muscle cell. d. The cytoplasm of a muscle cell. e. Area in muscle cell where Ca++ is stored and released. f. Collective name for all the T tubules. g. Expanded ends of sarcoplasmic reticulum; calcium storage sacs. h. A polysaccharide in muscle that stores energy. i. A protein in muscle that stores oxygen. j. Two terminal cisternae on each side of a T tubule. k. This part of muscle cell tranmits AP. l. Key unit of contraction composed of bundled parallel protein myofilaments. m. Functional unit of muscle contraction. n. The area along a myofibril between two adjacent Z lines. o. The thin myofilament. p. The thick myofilament. q. Dark area in middle of sarcomere; boundaries created by ends of myosin myofilaments. r. Lighter area in the middle of an A band; only myosins present. s. Light area of a sarcomere bisected by Z line, but thin myofilaments are main parts. 19. Approximately how many sarcomeres make up the average myofibril? 20. Draw and label the following parts on a sarcomere: Z lines, A band, I band. H zone, Myosin myofilaments, crossbridges, action myofilaments, and Titan proteins. 21. Draw a single myosin molecule and label the key parts. 22. Draw two myosin molecules, one in the high energy and one in the low energy states. 23. Approximately how many myosin molecules make up a myosin myofilament? 24. Name the 3 molecules found in the actin myofilament.
Bio 201 Tissues and Skin 3 February 23, 2011 25. Describe F actin; what does it look like? 26. What is the function of tropomyosin? 27. Name the 3 subunits of troponin and give the function of each. Subunit Function Subunit Function Subunit Function 28. What is titan and what function(s) does it have? 29. What is the difference between regulatory and contractile proteins in muscle? Give two examples of each. _ 30. What structural feature in skeletal muscle creates striations? 31. What 4 observations did Huxley and his coworkers make when a muscle cell contracted under the microscope? 32. Write an overview summary of what happens inside a muscle cell during a contraction. 33. Answer these specific questions regarding events in a muscle contraction. a. Before a contraction starts, the binding sites on the G actins are blocked by: b. What are calcium concentrations (high or low) in the sarcoplasm before the muscle cell contracts? c. What are calcium concentrations in the sarcoplasmic reticulum before the muscle cell contracts? d. What event causes calcium release from SR? e. What does calcium bind to in the sarcomere to trigger muscle contraction? f. What state (high or low energy) are the cross-bridges in before contraction begins? g. What are cross-bridges bonded to during a contraction? h. What are actin myofilaments anchored to? i. Cross-bridges in the high E state are attracted to exposed binding sites; an event called: j. After cross-bridges go to low energy state, what molecules are ejected from the cross-bridge? k. What causes cross-bridge (CB) detachment? l. What causes the CB to return to high energy state? m. Why is it important to detachment the CB? n.. What are calcium concentrations (high or low) in the sarcoplasm during the muscle cell contraction? o. What are calcium concentrations in the sarcoplasmic reticulum during the muscle cell contraction? p. What events cause a muscle cell to stop contracting? q. The changing of a CB from a high to low energy state is called the:
Bio 201 Tissues and Skin 4 February 23, 2011 r. A single power stroke causes what per cent reduction in sarcomere length? s. About what per cent of CBʼs operate at one time? t. How is calcium removed from the sarcoplasm when the AP stops? u. Where is the calcium sent to when it is removed from the sarcoplasm? 34. The stiffening of a body beginning 3 to 4 hours after death is called: 35. What specific event allows the body to stiffen after death? 36. Distinguish among an action potential, nerve impulse, and wave of depolarization. 37. What is a myoneural (= neuromuscular) junction? 38. The series of events by which electrical excitation of the sarcolemma leads to a contractions is called: 39. Identify the parts of a neuron and muscle cell based on the information provided. a. Small, numerous branches near the very end of the axon. b. Enlarged area housing nucleus and other key organelles. c. Elongate branch, usually, single, that extends from cell body. d. Receiving end and highly branched. e. Membrane-enclosed structures housing neurotransmitters. f. Major, 90 degree, branch of an axon. g. Swollen end of axon terminal. h. Nerve fiber. i. Space between synaptic end bulb and next cell. j. Another kind of nerve cell that envelopes and isolates myoneural junctions. k. The only kind of neurotransmitter associated with myoneural junctions involving skeletal muscle. l. Sites where neurotransmitters attach after their release. m. The enzyme that breaks down ACh. n. Highly folded area of muscle cell that houses receptors. 40. Answer the following questions regarding excitation-contraction coupling. a. When an action potential (AP) arrived at the synaptic end bulb (SEB) what happens? b. Synaptic vesicles release ACh by what process? c. By what process does ACh corss the synaptic cleft? d. Where are the receptors located that ACh binds to? e. If enough ACh binds to enough receptors what happens next? f. When an AP travels in a muscle cell where does it go and what happens as a result of the AP? g. Where does calcium come from in a skeletal muscle cell? h. What does calcium bind to after it is released into the sarcoplasm? i. What substance inactivates ACh? _ j. Why is this enzyme important? k. How does calcium return to the sarcoplasmic reticulum? l. What molecule is needed for both muscle contraction and relaxation?
Bio 201 Tissues and Skin 5 February 23, 2011 m. What molecule covers the active sites on the G actins when the muscle cell is not contracting? n. How many APʼs does it take from the neuron to initiate a muscle contraction? o. This autoimmune disease forms antibodies that attack ACh receptors. p. This chemical is derived from a S. American tree resin and is a competitive inhibitor with ACh. q. What is muscular dystrophy? 41. Define motor unit. 42. How many muscle cells, on average, are contacted by a single neuron? 43. How do fine control differ from strength control motor units? 44. What is the ratio of neuron to muscle cells in a: a. low ratio motior unit b. high ratio motor unit 45. A response by a muscle to a single, threshold stimulus is called a(n): 46. Draw a muscle twitch, label the phases, and label the axes of your graph. 47. Draw a slow and fast muscle twitches and label the axes of your graph.
Bio 201 Tissues and Skin 6 February 23, 2011 48. Draw a graph demonstrating Treppe with properly labeled axes. 49. Regarding Treppe answer the following questions. a. How does the voltage differ between twitches? b. How so does the second stimulus arrive after the first muscle twitch? _ c. Why does the tension increase with each successive twitch? 50. What is a graded response? 51. Are muscle twitches and treppe considered graded responses? 52. How does wave summation differ from Treppe? 53. How is wave summation similar to Treppe? 54. What is the difference between incomplete and complete tetany? 55. The inability of the muscle to contract due to depleted stores of ATP, CP, glycogen, and myoglobin is called: _ 56. In a multiple motor unit situation, what happens when the muscle has increasing amounts of voltage used to stimulate it? 57. Do all motor units have the same degree of excitability? 58. While some motor units are contracting, others are relaxing. This is called: 59. What is the advantage of this process named in question 58? 60. What is muscle tone? Why is it important? 61. An involuntary, painful, prolonged contraction is referred to as a(n). 62. List 5 potential situations that can cause cramping. 63. This type of muscle contraction develops tension, but the muscle does not change length. _ 64. This type of muscle contraction develops tensions and the muscle changes length. _
Bio 201 Tissues and Skin 7 February 23, 2011 65. How do concentric and eccentric muscle contractions differ? 66. What is the optimal muscle cell length (in % above and below) in skeletal muscle? What structural feature makes this length optimal for generating tension? 67. If the skeletal muscle cell is too long, what happens structurally to prevent it from generating full tension? 68. If the skeletal muscle cell is too short, what happens structurally to prevent it from generating full tension? 69. How do anaerobic and aerobic respirations differ? What do they use to run their pathways and what are their waste products? 70. Write the equation and the enzyme for the breakdown and synthesis of ATP. 71. Write the two equations and their enzymes for the reattachment of a phosphate (Pi) to an ADP. 72. How long do the ATPʼs reserves in a muscle last when under maximum use? 73. How long does the phosphagen system last when under maximum use? 74. Assuming little to no oxygen reaching a contracting muscle, what other energy rich molecule is used to keep muscles contracting? 75. What are 4 factors that limit the ability of a muscle to keep contracting without oxygen? 76. Why are fats a poor source of energy in a rapidly contracting muscle? 77. Why are fats a good source of energy in a muscle with normal activity? 78. Answer the questions about glycolysis. a. What is glycogen? b. What is the initial substrate of glycolysis? c. What is the endproduct of glycolysis? d. How many net ATPs come from glycolysis? e. How many reduced NADʼs come from glycolysis? f. What part of the cell uses these reduced NADʼs to generate energy? g. If oxygen is available, what happens to the endproduct? h. If oxygen is absent, what happens to the endproduct? i. How is lactic acid important to keeping glycolysis running? 79. Answer the following questions about the Bridge Reaction and Krebʼs Cycle. a. What substrate enters the bridge reaction? b. What is the endproduct of the bridge reaction or the substrate for the Krebʼs Cycle? c. What energy-rich molecule comes from the Bridge reaction (BR)? d. What waste product comes from the Bridge Reaction? e. How many carbons does the substrate come in with and how many carbons does the endproduct possess? f. At the start of the Krebʼs cycle are two molecules. How big (in terms of carbons) are these two molecules. g. What is the name of the bigger molecule formed from the two combined molecules in question ʻfʼ? h. How many net ATPʼs does the Krebʼs Cycle (KC) form from each pyruvate that enters? i. How many net reduced NADʼs does the KC form from each pyruvate that enters? j. How many net reduced FADʼs does the KC form from each pyruvate that enters? k. How many pyruvates come from each glucose molecule?
Bio 201 Tissues and Skin 8 February 23, 2011 l. How many total reduced NADs come from the BR and KC for each glucose that starts in glycolysis? m. How many total reduced FADs come from the BR and KC for each glucose that starts in glycolysis? n. How many total ATPs come from the BR and KC for each glucose that starts in glycolysis? o. What happens to the reduced NADs and FADs formed from the BR and KC? p. What part of the cell uses these reduced NADʼs and FADs to generate energy? 80. Write a summary of what the Electron Transport System (ETS) does with the reduced NADs and FADs. What is the process called? 81. Compare aerobic and anaerobic pathways with regard to the breakdown of glucose, amount of ATPʼs formed per glucose, and time to produce the glucoses. 82. The physiological inability of a muscle to contract is called: 83. What 4 factors that contribute to muscle fatigue? 84. How specifically does lactic acid cause muscleʼs to fatigue? 85. How do ionic imbalances caused muscle fatigue? 86. How is the nervous system inhibited during muscle fatigue? 87. How does depletion of myoglobin reserves contribute to muscle fatigue? 88. What is oxygen debt? 89. Which kind of exercise is going to produce the most lactic acid, sprinting or marathon running? Why? 90. What is the basic difference between fast and slow twitch muscle fibers? 91.Identify the kind of skeletal muscle fiber (Slow-twitch reds, Fast-twitch reds, or fast-twitch whites) based on the information provided. a. Contraction velocity ~ 50 msec. b. Contraction velocity ~ 100 msec. c. Deficient in capillaries, mitochondria, but rich in glycogen. d. Most resistant to fatigue, rich in mitochondria and capillaries. e. Very dark muscle color. f. Lightest muscle color. g. Postural muscles, soleus. h. Eye muscles and hands. i. Least resistant to fatigue. j. Uses almost entirely aerobic respiration. k. Most adapted to running muscle action anaerobically. 92. By what anatomical changes do muscles increase in size during weight training? 93. How does endurance training affect the anatomical structure of muscle? 94. What is atrophy and hypertrophy with regard to muscle?
Bio 201 Tissues and Skin 9 February 23, 2011 95. Identify the condition of smooth muscle with regard to the listed structures or information. a. Striations. _ b. Sarcomeres. _ c. Z lines (discs). _ d. SR. _ e. T Tubules. _ f. Source of Calcium. _ g. Gap junctions. _ h. Nerve supply. _ 96. What do the acting myofilaments attach to in smooth muscle? 97. Contraction of two sheets of smooth muscle in an alternating sequence is called: _ 98. What are bulbous varicosities? 99. List 3 characteristics that both skeletal and smooth muscle share. _ 100. Identify the kind of smooth muscle from the information provided. a. Electrically coupled by gap junctions. _ b. Independent contraction of muscle fibers. _ c. Usually arranged in two layers for peristalsis. _ d. Most of internal viscera is of this type. _ e. Arrector pili, largest arteries and airways. _ 101. What are pacemaker cells with regard to smooth muscle? 102. What are the two main neurotransmitters affecting smooth muscle? 103. Describe how calcium triggers the activation of a smooth muscle cell contraction. 104. Describe the shape of a smooth muscle cell after it contracts. 105. Compare smooth muscle to skeletal muscle with regard to contraction rate and energy use. 106. What is vasomotor tone? 107. What is the stretch-relaxation response? Why is this advantageous for organs with smooth muscle? 108. Smooth muscle cells can divide and increase in number, a characteristic called: 109. Smooth muscle can form new cells, contractile proteins, elastin, and collagen, a characteristic called: 110. Compare the length-tension relationship of smooth to skeletal muscle. 111. What is muscular dystrophy and what is it structural cause? 112. What is an autoimmune disease? 113. What is myasthenia gravis, what are some symptoms, what is a treatment, and what happens anatomically to cause the symptoms?
Bio 201 Tissues and Skin 10 February 23, 2011