SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.Figure 9.1Using Figure 9.1, match the following:1)Endomysium.1)2)Fascicle.2)3)The tissue that binds muscles into functional groups.3)4)Perimysium.4)5)Muscle fiber.5)1Figure 9.2Using Figure 9.2, match the following:6)I band.6)7)H zone.7)8)A band.8)9)Z disc.9)10)M line.10)MATCHING. Choose the item in column 2 that best matches each item in column 1.Match the following:11)Depends on oxygen delivery andaerobic mechanisms.12)Have very fast-acting myosinATPases and depend upon anaerobicmetabolism during contraction.13)Red fibers, the smallest of the fibertypes.A)Slow (oxidative), fatigue-resistant fibersB)Fast (oxidative or glycolytic), fatigablefibers11)12)13)214)Contain abundant amounts ofglycogen.15)Abundant in muscles used to maintainposture.16)A relatively high percentage are foundin successful marathon runners.A)Slow (oxidative), fatigue-resistant fibersB)Fast (oxidative or glycolytic), fatigablefibers14)15)16)Match the following:17)The stimulus above which no strongercontraction can be elicited, because allmotor units are firing in the muscle.18)The phenomenon in which thecontraction strength of a muscleincreases, due to increased Ca2+availability and enzyme efficiencyduring the warm-up.19)Continued sustained smoothcontraction due to rapid stimulation.20)The situation in which contractionsbecome stronger due to stimulationbefore complete relaxation occurs.21)How a smooth increase in muscleforce is produced.A)Wave summationB)Multiple motor unit summationC)TetanusD)TreppeE)Maximal stimulus17)18)19)20)21)Match the following:22)A sarcomere is the distance betweentwo ________.23)The ________ contains only the actinfilaments.24)The thicker filaments are the ________filaments.25)Both actin and myosin are found in the________.26)The myosin filaments are located inthe ________.A)I bandB)A bandC)MyosinD)Z discs22)23)24)25)26)3Match the following:27)Serves as the actual "trigger" formuscle contraction by removing theinhibition of the troponin molecules.28)A neurotransmitter released at motorend plates by the axon terminals.29)Diffusion across the cell membraneresults in depolarization.30)Activate synaptic vesicles in axonterminals.31)Used to convert ADP to ATP bytransfer of a high-energy phosphategroup. A reserve high-energycompound.32)Destroys ACh.A)Sodium-potassium ionsB)AcetylcholineC)Calcium ionsD)AcetylcholinesteraseE)Creatine phosphate27)28)29)30)31)32)TRUE/FALSE. Write 'T' if the statement is true and 'F' if the statement is false.33)Once a motor neuron has fired, all the muscle fibers in a muscle contract.33)34)The thin filaments (actin) contain a polypeptide subunit G actin that bears active sites for myosinattachment.34)35)The force of muscle contraction is controlled by multiple motor unit summation or recruitment.35)36)Eccentric contractions are more forceful than concentric contractions.36)37)A motor neuron and all the muscle cells that it stimulates are referred to as a motor end plate.37)38)Peristalsis is characteristic of smooth muscle.38)39)A contraction in which the muscle does not shorten but its tension increases is called isometric.39)40)During isotonic contraction, the heavier the load, the faster the velocity of contraction.40)41)During isometric contraction, the energy used appears as movement.41)42)One of the important functions of skeletal muscle contraction is production of heat.42)43)An increase in the calcium ion level in the sarcoplasm starts the sliding of the thin filaments. Whenthe level of calcium ions declines, sliding stops.43)44)Muscle contraction will always promote movement of body parts regardless of how they areattached.44)445)Although there are no sarcomeres, smooth muscle still possesses thick and thin filaments.45)46)Muscle tone is the small amount of tautness or tension in the muscle due to weak, involuntarycontractions of its motor units.46)47)Single-unit smooth muscle is found in the intestines.47)48)A resting potential is caused by a difference in the concentration of certain ions inside and outsidethe cell.48)49)The effect of a neurotransmitter on the muscle cell membrane is to modify its ion permeabilityproperties temporarily.49)50)When a muscle fiber contracts, the I bands diminish in size, the H zones disappear, and the Abands move closer together but do not diminish in length.50)51)Contractures are a result of a total lack of ATP.51)52)Smooth muscles relax when intracellular Ca2+ levels drop but may not cease contractions.52)MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.53)What is the role of tropomyosin in skeletal muscles?A)Tropomyosin serves as a contraction inhibitor by blocking the myosin binding sites on theactin molecules.B)Tropomyosin is the name of a contracting unit.C)Tropomyosin serves as a contraction inhibitor by blocking the actin binding sites on themyosin molecules.D)Tropomyosin is the receptor for the motor neuron neurotransmitter.53)54)Which muscle cells have the greatest ability to regenerate?A)cardiacB)no muscle can regenerateC)skeletalD)smooth54)55)Most skeletal muscles contain ________.A)muscle fibers of the same typeB)a predominance of fast oxidative fibersC)a predominance of slow oxidative fibersD)a mixture of fiber types55)56)Fatigued muscle cells that recover rapidly are the products of ________.A)slow exercise of long durationB)intense exercise of long durationC)intense exercise of short durationD)slow exercise of short duration56)57)The strongest muscle contractions are normally achieved by ________.A)increasing the stimulation up to the maximal stimulusB)recruiting small and medium muscle fibersC)increasing stimulus above the thresholdD)increasing stimulus above the treppe stimulus57)558)Which of the following would be recruited later in muscle stimulation when contractile strengthincreases?A)many small motor units with the ability to stimulate other motor unitsB)large motor units with small, highly excitable neuronsC)motor units with the longest muscle fibersD)motor units with larger, less excitable neurons58)59)Which of the following is not a usual result of resistance exercise?A)increase in the number of myofibrils within the muscle cellsB)increase in the number of muscle cellsC)increase in the efficiency of the respiratory systemD)increase in the efficiency of the circulatory system59)60)Excitation-contraction coupling requires which of the