Chapter 11 Muscle Tissue

82) When acetylcholine binds to receptors at the motor end plate, the muscle membrane becomes A) More permeable to sodium ions. B) Less permeable to sodium ions. C) More permeable to potassium ions. D) Less permeable to potassium ions. E) Repolarized

A) More permeable to sodium ions.

10) *Cell membrane of skeletal muscle* is called the A) Sarcolemma. B) Sarcomere. C) Sarcosome. D) Sarcoplasmic reticulum. E) Sarcoplasm.

A) Sarcolemma.

59) Which of the following is Not characteristic of smooth muscle? A) Smooth muscle connective tissue forms tendons and aponeuroses. B) Neurons that innervate smooth muscles are under involuntary control. C) Smooth muscles are uninucleate. D) Smooth muscles do not contain sarcomeres. E) The thin filaments of smooth muscle fibers are attached to dense bodies.

A) Smooth muscle connective tissue forms tendons and aponeuroses.

33) *When calcium ion binds to troponin*, A) Tropomyosin moves out of the groove between the actin molecules B) Actin sites on the myosin are exposed C) Actin heads will bind to myosin D) Muscle relaxation occurs E) Myosin shortens

A) Tropomyosin moves out of the groove between the actin molecules

37) The type of contraction represented by a single stimulus/contraction/relaxation sequence is a(n) A) Twitch. B) Incomplete tetanus. C) Complete tetanus. D) Summation. E) Incomplete summation

A) Twitch. *(short, sudden jerking)*

16) *Thin filaments at either end of the sarcomere* are attached to the A) Z line. B) M line. C) H band. D) A band. E) I band

A) Z line.

87) Which of the following muscles would produce the greater tension? A) a muscle with 20 motor units active B) a muscle with 10 motor units active

A) a muscle with 20 motor units active

57) Heat energy produced from muscle contraction is released through the ________ system. A) integumentary B) respiratory C) cardiovascular D) urinary E) digestive

A) integumentary *(Heat is release through the Skin - integumentary)*

54) *Fast muscle* fibers can develop a larger number of mitochondria in response to A) repeated, exhaustive stimulation B) sustained low levels of muscle a activity C) high amounts of oxygen D) increased levels of testosterone E) prolonged periods of inactivity

A) repeated, exhaustive stimulation

52) Contraction that utilize anaerobic ATP production A) require maximal contraction of muscles for short periods of time B) do not use ATP very quickly C) rely on slow muscle fibers D) do not rely on the energy reserve of creatine phosphate

A) require maximal contraction of muscles for short periods of time

The length of time a muscle can continue to contract while *supported by mitochondrial* activities

*Aerobic* Endurance

The Length of time muscular contraction can continue to be *supported by Glycolysis* and by the existing *energy reserves* of ATP & CP

*Anaerobic* Endurance

88) Decreased blood flow to a muscle could result in all of the following, EXCEPT A) Fatigue. B) An oxygen debt. C) An increase in intracellular glycogen. D) A shift to more anaerobic glycolysis in the muscle. E) An increase in intracellular lactate.

C) An increase in intracellular glycogen.

41) A muscle that is stimulated so frequently that the relaxation phase is *complete*ly eliminated is said to exhibit A) Incomplete tetanus. B) Complete tetanus. C) Treppe. D) Wave summation. E) Recruitment.

B) *Complete* Tetanus.

76) Because skeletal muscle contractions demand large quantities of ATP, skeletal muscles have A) A rich nerve supply. B) A rich vascular supply. C) Very few mitochondria. D) Little need for oxygen. E) A large concentration of tissue hemoglobin.

B) A rich vascular supply.

22) The skeletal muscle complex known as the *Triad* consists of A) Actin, myosin, and filaments. B) A transverse tubule and terminal cisternae. C) Filaments, myofibrils, and sarcomeres. D) A bands, H bands, and I bands. E) Actin, myosin, and sarcomeres

B) Transverse tubule & Terminal cisternae.

86) Which of the following muscles would contract more forcefully? A) a muscle receiving 5 action potentials per second B) a muscle receiving 10 to 15 action potentials per second

B) a muscle receiving 10 to 15 action potentials per second

99) During muscle contraction, myosin cross bridges attach to active sites of: A) myosin filaments B) actin filaments C) Z lines D) thick filaments E) the H zone

B) actin filaments

47) When energy reserves in a muscle are exhausted & lactic acid levels increase, ________ occurs. A) an oxygen debt B) fatigue C) treppe D) tetanus E) atrophy

B) fatigue

51) The type of muscle fiber that is most resistant to fatigue is the _____ fiber A) fast B) slow C) anaerobic D) intermediate E) high-density

B) slow

78) Which of the following is greater? A) the concentration of calcium ion in the sarcoplasmic reticulum of a resting muscle B) the concentration of calcium ion in the sarcoplasm of a resting muscle

A) the concentration of calcium ion in the sarcoplasmic reticulum of a resting muscle

9) *Skeletal muscle* fibers are formed from *embryonic cells* called A) Sarcomeres. B) Myofibrils. C) Myoblasts. D) Fascicles. E) Myomeres

C) *Myoblasts*.

24) At rest, active sites on the *Actin* are blocked by A) Myosin molecules. B) Troponin molecules. C) Tropomyosin molecules. D) Calcium ions. E) ATP molecules

C) *Tropomyosin* molecules. *(Actin->Tropomyosin->Troponin)*

17) The *area* of the sarcomere *containing the thick filaments* is the A) Z line. B) M line. C) A band. D) I band.

C) A band.

69) In the neurons that innervate skeletal muscles, the cytoplasm of the synaptic terminal contains mitochondria and vesicles filled with molecules of the* neurotransmitter* A) Epinephrine. B) Norepinephrine. C) Acetylcholine. D) Antidiuretic hormone. E) all of the above

C) Acetylcholine.

45) *Creatine* phosphate A) Is produced by the process of anaerobic respiration. B) Can replace ATP in binding to myosin molecules during contraction. C) Acts as an energy reserve in muscle tissue. D) Is only formed during strenuous exercise. E) Cannot transfer its phosphate group to ADP.

C) Acts as an *Energy Reserve* in muscle tissue.

49) During the recovery period the body's need for oxygen is increased because A) Muscle cells are producing energy anaerobically. B) The individual is panting. C) Additional oxygen is required to metabolize the lactic acid produced during exercise. D) The liver requires more oxygen to produce lactic acid. E) The muscles are not producing ATP.

C) Additional oxygen is required to metabolize the lactic acid produced during exercise.

44) A resting muscle *generates most of its ATP* by A) Conversion of creatine phosphate. B) Anaerobic respiration. C) Aerobic respiration. D) Glycogenolysis. E) The tricarboxylic acid cycle.

C) Aerobic respiration. *(Aerobic produce most ATP)*

31) In response to action potentials arriving from the transverse tubules, the *Sarcoplasmic Reticulum releases* A) Acetylcholine. B) Sodium ions. C) Potassium ions. D) Calcium ions E) Hydrogen ions.

D) Calcium ions

21) *Sarcoplasmic Reticulum stores* A) Oxygen. B) Glycogen. C) ATP. D) Calcium ions. E) Glucose.

D) Calcium ions.

89) Increased oxygen consumption would accompany all of the following, except A) Increased heat production. B) Increased conversion of lactate to glucose. C) Increased aerobic respiration by muscle cells. D) Decreased ATP use. E) Increased muscle activity

D) Decreased ATP use.

91) How would a drug that competes with acetylcholine for receptors at the motor end plate affect skeletal muscle? A) It would make the muscles more excitable. B) It would produce uncontrolled muscle spasms. C) It would cause spastic paralysis (muscles are contracted and unable to relax). D) It would cause flaccid paralysis (muscles are relaxed and unable to contract). E) It would have no effect on skeletal muscles.

D) It would cause flaccid paralysis (muscles are relaxed and unable to contract).

93) The bacterium that causes *tetanus* produces a toxin that affects the central nervous system & skeletal muscles, producing powerful *Tetanic contractions* of the skeletal muscles. The toxin probably acts by A) Increasing the amount of acetylcholinesterase in the synapse. B) Making the cells less permeable to sodium ions. C) Increasing the amount of potassium ion in the intercellular fluid. D) Making the cell membranes more permeable to calcium ion. E) Competing with acetylcholine for receptors at the motor end plate.

D) Making the cell membranes more permeable to calcium ion.

56) Each of the following changes in the skeletal muscles is a consequence of aging, Except A) Muscle fibers become smaller in diameter B) Muscles become less elastic. C) Muscles fatigue more rapidly. D) Muscle fibers increase their reserves of glycogen. E) There is a steady decrease in the number of satellite cells.

D) Muscle fibers increase their reserves of glycogen.

61) The ability of smooth muscle to function over a *wide range of lengths* is called A) Elasticity. B) Contractility. C) Extensibility. D) Plasticity. E) Variability.

D) Plasticity *(Quality of being easily shaped / molded)*

80) *After death*, muscle fibers run out of ATP and calcium begins to leak from the sarcoplasmic reticulum into the sarcoplasm. This results in a condition known as A) Tetany. B) Treppe. C) Depolarization. D) Rigor mortis. E) Oxygen debt.

D) Rigor mortis.

27) The space between the neuron & muscle is the A) Synaptic knob. B) Motor end plate. C) Motor unit. D) Synaptic cleft. E) M line

D) Synaptic cleft. *(Space - Cleft)*

32) Which of the following acts as an *ATP*ase during the contraction cycle of muscle? A) actin molecules B) troponin molecules C) tropomyosin molecules D) myosin cross-bridges E) the tail portion of the myosin molecule

D) myosin cross-bridges *(ATP like MRT cross bridge)*

101) Creatine phosphate functions in the muscle cell by: A) forming a temporary chemical compound with myosin B) forming a chemical compound with actin C) inducing a conformational change in the myofilaments D) storing energy that will be transferred to ADP to resynthesize ATP as needed E) storing energy that will be transferred to ATP to resynthesize ADP as needed

D) storing energy that will be transferred to ADP to resynthesize ATP as needed

96) Which of the following is NOT a function of the muscular system: A) producing movement B) maintaining posture C) stabilizing joints D) generating heat E) hematopoiesis

E) *Hematopoiesis 造血*

43) The type of contraction in which the muscle fibers produce increased tension but *Do Not Shorten* is called A) Tetany. B) Treppe. C) Concentric D) Isotonic. E) Isometric

E) *Isometric (Do Not Shorten = Same Length ISO = Same Metric = Length)*

36) *Calcium* ions are *released* from the Sarcoplasmic Reticulum during the ________ of contraction. A) latent period B) contraction phase C) recovery phase D) relaxation phase E) A and B

E) A & B Latent Period. Contraction Phase.

50) Fast fibers A) Have high resistance to fatigue B) Have a low concentration of myoglobin C) Have many mitochondria D) Produce powerful contraction E) Both B and D

E) Both B & D Have a low concentration of myoglobin. Produce powerful contraction.

77) During muscle contraction, all of the following occur, *Except* A) ATP is hydrolyzed. B) Myosin heads bind to actin. C) The H band becomes shorter. D) Calcium concentration in the sarcomere increases. E) Hemoglobin concentration in muscle fibers increases.

E) Hemoglobin concentration in muscle fibers increases.

18) The *area* of the sarcomere that contains *ONLY thin filaments* is the A) Z line. B) M line. C) H band. D) A band. E) I band

E) I band (I is Thin)

42) The increase in muscle tension that is produced by *increasing* the number of active motor units is called A) Incomplete tetanus. B) Complete tetanus. C) Treppe. D) Wave summation. E) Recruitment

E) Recruitment *(Increasing by Recruiting more)*

11) *Cytoplasm of a skeletal muscle* fiber is called the A) Sarcolemma. B) Sarcomere. C) Sarcosome. D) Sarcoplasmic reticulum. E) Sarcoplasm

E) Sarcoplasm

97) A motor unit consists of: A) a skeletal muscle and all the neurons that supply it B) a nerve and all of the skeletal muscles supplied by it C) all of the neurons that stimulate a single action D) all of the skeletal muscles that accomplish a single movement E) a neuron and all of the skeletal muscle fibers that it stimulates

E) a neuron and all of the skeletal muscle fibers that it stimulates

98) Acetylcholine is: A) an ion pump B) a source of energy for muscle contraction C) a component of thick myofilaments D) an oxygen binding protein E) a neurotransmitter

E) a neurotransmitter

63) In order for a muscle to contract properly, it requires A) Energy. B) Oxygen. C) Nutrients. D) An adequate blood supply. E) all of the above

E) all of the above

67) When a skeletal muscle fiber contracts, A) The H zones and I bands get smaller. B) The zones of overlap get larger. C) The Z lines get closer together. D) The width of the A band gets constant. E) all of the above

E) all of the above

55) Which of the following statements are true regarding human muscles? A) All human muscles have both slow and fast fibers. B) Fast fibers are found in the calf muscles. C) Eye and hand muscles are composed of fast fibers. D) Back muscles are mostly composed of endurance fibers. E) both C and D

E) both C and D

66) Each skeletal muscle fiber contains ________ *myofibrils*. A) 50 to 100 B) 100 to 150 C) 150 to 200 D) 200 to 500 E) hundreds to thousands

E) hundreds to thousands

100) A muscle twitch differs from a tetanic contraction in that: A) the tetanic contraction is considered abnormal, while the twitch is a normal muscle response B) the tetanic contraction is caused by a single stimulus, while the twitch is caused by very rapid multiple stimuli C) the muscle twitch is prolonged and continuous while a tetanic contraction is brief and jerky D) the muscle twitch occurs only in small muscles while a tetanic contraction occurs in large muscle groups E) the muscle twitch is a brief and jerky movement, while the tetanic contraction is prolonged and continuous

E) the muscle twitch is a brief and jerky movement, while the tetanic contraction is prolonged and continuous

30) Active sites on the *Actin become available for binding when* A) Actin binds to troponin. B) Troponin binds to tropomyosin. C) Calcium binds to troponin. D) Calcium binds to tropomyosin. E) Myosin binds to troponin.

C) Calcium binds to troponin.

73) Large diameter, densely packed myofibrils, large glycogen reserves, and few mitochondria are characteristics of A) Slow fibers. B) Intermediate fibers. C) Fast fibers. D) Red muscles. E) Fatty muscles

C) Fast fibers.

62) At each end of the muscle, the collagen fibers of the epimysium, perimysium, & endomysium come together to form either a bundle known as a ________, or a broad sheet called an *Aponeurosis*. A) tendon B) satellite cells C) joint D) fascicle E) none of the above

A) *Tendon. Aponeurosis: sheetlike tendinous expansion*

20) Each thin filament consists of A) A pair of protein strands wound together. B) Chains of myosin molecules. C) 6 molecules coiled into a helical structure. D) A rod-shaped structure with "heads" projecting from each end. E) A double strand of myosin molecules.

A) A pair of protein strands wound together.

5) The delicate connective tissue that *surrounds the skeletal muscle fibers & TIES ADJACEMENT muscle fibers together* is the A) Endomysium. B) Perimysium. C) Epimysium. D) Superficial fascia. E) Periosteum.

A) Endomysium.

39) A muscle producing peak tension with *rapid cycles* of contraction & relaxation is said to be in A) Incomplete tetanus. B) Complete tetanus. C) Treppe. D) Wave summation. E) Recruitment

A) Incomplete tetanus. *(Rapid, Too Fast, Incomplete)*

Reduction in muscle size, tone, & power is called _____

Atrophy

34) The most important factor in decreasing the intracellular concentration of calcium ion *after contraction* is A) Active transport of calcium across the sarcolemma. B) Active transport of calcium into the sarcoplasmic reticulum. C) Active transport of calcium into the synaptic cleft. D) Diffusion of calcium out of the cell. E) Diffusion of calcium into the sarcoplasmic reticulum.

B) Active transport of calcium into the sarcoplasmic reticulum.

74) Physical evidence that supports the sliding filament theory of muscle contraction includes A) Increased width of the H band during contraction. B) Decreased distance between Z lines during contraction. C) Increased width of the I band during contraction. D) Decreased width of the A band during contraction. E) An increased distance between Z lines during contraction.

B) Decreased distance between Z lines during contraction.

3) The dense layer of collagen fibers that *surround an ENTIRE skeletal muscle* is the A) Tendon. B) Epimysium. C) Endomysium. D) Perimysium. E) Fascicle.

B) Epimysium.

7) Muscle fibers differ from "typical cells" in that muscle fibers A) Lack a cell membrane. B) Have many nuclei. C) Are very small. D) Lack mitochondria. E) both B and C

B) Have many nuclei.

15) In a sarcomere, *Thick Filaments are linked by* A) Z line. B) M line. C) H band. D) A band. E) I band.

B) M line.

28) *Receptors for Acetylcholine* are located on A) Synaptic knob. B) Motor End Plate. C) Sarcomere. D) Synaptic cleft. E) Transverse tubule

B) Motor end plate.

23) *Cross-Bridges* are portions of A) Actin molecules. B) Myosin molecules. C) Troponin molecules. D) Tropomyosin molecules. E) Calcium ions

B) Myosin molecules. *(I me My Cross the Bridge)*

4) *Nerves & Blood Vessels* that service the muscle fibers are located in the connective tissues of the A) Endomysium. B) Perimysium. C) Sarcolemma. D) Sarcomere. E) Myofibrils

B) Perimysium.

13) *Functional unit* of a *skeletal* muscle fiber is the A) Sarcolemma. B) Sarcomere. C) Sarcoplasmic reticulum. D) Myofibril. E) Myofilament

B) Sarcomere.

12) The series of *membranous channels that surround each myofibril* is the A) Sarcolemma. B) Sarcoplasmic reticulum. C) Myolemma. D) Sarcoplasm. E) Transverse tubule.

B) Sarcoplasmic reticulum.

6) The bundle of collagen fibers at the end of a skeletal muscle that attaches the *muscle to bone *is called a(n) A) Fascicle. B) Tendon. C) Ligament. D) Epimysium. E) Myofibril

B) Tendon.

71) In an *isotonic contraction*, A) Muscle tension exceeds the resistance and the muscle shortens. B) Tension rises and the skeletal muscle length changes. C) The peak tension developed is less than the resistance. D) The muscle as a whole does not change length. E) all of the above

B) Tension rises (Remain Constant) & the skeletal muscle length changes.

79) When myosin *cross-bridges* bind to the active sites on actin, A) ATP is hydrolyzed. B) They pivot toward the M line. C) The sarcomere strengthens. D) Muscle relaxation occurs. E) The I band moves closer to the Z line.

B) They pivot toward the *M* line. *(I, me, my cross-bridges)*

60) Which of the following is Not a function of smooth muscle tissue A) Altering the diameter of the respiratory passageway B) Elevating hairs on the arm C) Forcing blood from the heart into the major arteries D) Moving food materials along the digestive tract E) Forcing urine out of the urinary tract

C) Forcing blood from the heart into the major arteries

19) *Area* in the center of the A band that contains *ONLY thick filaments* is the A) Z line. B) M line. C) H band. D) I band. E) Zone of overlap.

C) H band. *(H is Strong & Thick)*

81) How would blocking the activity of acetylcholinesterase affect skeletal muscle? A) It would make the muscles less excitable. B) It would produce muscle weakness. C) It would cause spastic paralysis (muscles are contracted and unable to relax). D) It would cause flaccid paralysis (muscles are relaxed and unable to contract). E) It would have no effect on skeletal muscles.

C) It would cause spastic paralysis (muscles are contracted and unable to relax).

90) How would an elevated level of *Thyroid hormone* in the body affect skeletal muscles? A) It would stimulate atrophy. B) It would stimulate hypertrophy. C) It would stimulate metabolism. D) It would decrease heat production by muscle tissue. E) It would cause an increase in muscle mass.

C) It would stimulate metabolism (Thyroid for Metabolism)

14) Interactions between *Actin & Myosin filaments* of the sarcomere are *responsible for* A) Muscle fatigue. B) The conduction of neural stimulation to the muscle fiber. C) Muscle contraction. D) Muscle relaxation. E) The striped appearance of skeletal muscle.

C) Muscle contraction.

48) During the recovery period following exercise, all of the following are true, except A) Lactic acid is removed from muscle cells. B) The muscle actively produces ATP. C) Muscle fibers remain contracted. D) Oxygen is consumed. E) Heat is generated.

C) Muscle fibers remain contracted.

72) The contraction of a muscle exerts a pull on a bone because A) Muscles are attached to bones by ligaments. B) Muscles are directly attached to bones. C) Muscles are attached to bones by tendons. D) A, B, and C E) none of the above

C) Muscles are attached to bones by Tendons. *(Muscle-Bone: Tendon Bone-Bone: Ligament)*

26) *Each skeletal muscle fiber is controlled by* a neuron at a single A) Synaptic knob. B) Sarcomere. C) Neuromuscular junction. D) Synaptic cleft. E) Transverse tubule

C) Neuromuscular junction.

35) Which of the following statements is incorrect A) When sarcomeres are fully shortened, contraction cannot occur B) When sarcomeres are slightly less than fully shortened, contraction cannot occur C) Sarcomeres can produce the most tension when stimulated over a relatively wide range of resting lengths D) When the muscle is fully stretched, contraction cannot occur E) All sarcomeres in a muscle fiber contract and relax together

C) Sarcomeres can produce the most tension when stimulated over a relatively wide range of resting lengths

2) Which of the following statements is incorrect? A) The contractions of skeletal muscles pull on tendons and move bones of the skeleton. B) Skeletal muscles are responsible for controlling the openings of the digestive and urinary tracts. C) Skeletal muscles are responsible for the pumping action of the heart. D) Skeletal muscles support the weight of some internal organs. E) Skeletal muscle contractions help maintain body temperature

C) Skeletal muscles are responsible for the pumping action of the heart. *(pumping action of the heart is Smooth Muscle; Not Skeletal muscle)*

92) If a person was suffering from severe *Hyperkalemia*, you would expect A) The potassium ion concentration of the interstitial fluid to be less than normal. B) The membrane potential of nerves and muscles to be more negative. C) Skeletal muscles to be unresponsive and the heart muscle would undergo cardiac arrest. D) Muscle weakness and increased strength of twitch contractions. E) both A and D

C) Skeletal muscles to be unresponsive & heart muscle would undergo cardiac arrest. *Hyperkalemia* is a medical emergency, due to the risk of potentially fatal *Abnormal Heart rhythms*

75) Which of the following hormones directly stimulates growth of muscle tissue and increased muscle mass? A) Epinephrine. B) Thyroid hormone. C) Testosterone. D) Parathyroid hormone. E) Calcitonin.

C) Testosterone.

64) *Skeletal muscle contracts only *under stimulation from A) The sympathetic nervous system. B) The parasympathetic nervous system. C) The Central Nervous System. D) all of the above E) none of the above

C) The central nervous system.

29) *Action potentials are conducted* into a skeletal muscle fiber by A) Motor end plates. B) Neuromuscular junctions. C) Transverse tubules. D) Triads. E) Sarcoplasmic reticulum

C) Transverse tubules. *(Action potentials are conducted by T-Tubule)*

94) Athletes usually go through a "warm-up" period before engaging in an event. The reason for this "warm-up" period would be to take advantage of A) Incomplete tetanus. B) Complete tetanus. C) Treppe. D) Wave summation. E) Recruitment.

C) Treppe.

25) At rest, the *Tropomyosin* molecule is held in place by A) Actin molecules. B) Myosin molecules. C) Troponin molecules. D) ATP molecules. E) Calcium ions.

C) Troponin molecules.

53) during activates requiring *Aerobic* endurance A) glycogen and glycolysis are the primary source of reserve energy B) oxygen debts are common C) most of the muscle's energy is produced in mitochondria D) fatigue occurs in a few minutes E) oxygen is not required

C) most of the muscle's energy is produced in mitochondria *(Aerobic use ATP mitochondria)*

84) In which of the following would the ratio of motor neurons to muscle fibers be the greatest? A) large muscles of the upper arms B) postural muscles of the back C) muscles that control the eye D) leg muscles E) the calf muscle

C) muscles that control the eye *(eye too fast, need more neurons)*

70) ATP metabolism normally provides ________ percent of the ATP demands of a resting cell. A) 25 B) 50 C) 70 D) 95 E) 100

D) 95

85) When contraction occurs, A) The H and I bands get smaller. B) The width of the A band remains constant. C) The Z lines move closer together. D) A, B, and C E) none of the above

D) A, B, and C

68) The pull called tension is a (n) ________ force. A) Passive B) Assertive C) Aggressive D) Active E) all of the above

D) Active

8) The advantage of having many nuclei in a skeletal muscle fiber is A) The ability to contract. B) The ability to produce more ATP with little oxygen. C) The ability to repair the fiber after an injury. D) The ability to produce large amounts of the enzymes and structural proteins needed for contraction. E) both B and C

D) The ability to produce large amounts of the enzymes and structural proteins needed for contraction.

38) When a muscle is stimulated repeatedly for several seconds with a constant stimulus, the amount of *tension gradually increases* to a maximum. This phenomenon is called A) Incomplete tetanus. B) Complete tetanus. C) A twitch. D) Wave summation. E) Recruitment

D) Wave summation.

40) If a second stimulus arrives before the relaxation phase has ended, a second, *more powerful contraction occurs*. This is called A) Incomplete tetanus. B) Complete tetanus. C) Treppe. D) Wave summation. E) Recruitment.

D) Wave summation.

102) *Muscle tone* is: A) the feeling of well-being following exercise B) the ability of a muscle to maintain a contraction against an outside force C) the condition of athletes after intensive training D) a state of sustained partial muscular contraction that is vital for the health of muscles E) the result of increased neuromuscular system coordination and increased metabolic rate

D) a state of sustained partial muscular contraction that is vital for the health of muscles

46) During Anaerobic *Glycolysis* A) ATP is produced. B) Pyruvic acid is produced. C) Lactic acid is produced if pyruvic acid accumulates. D) all of the above E) A and B only

D) all of the above

1) Which of the following is not a function of skeletal muscle? A) produce movement B) maintain posture C) maintain body temperature D) all of the above are functions of the skeletal muscle E) A and B only

D) all of the above are functions of the skeletal muscle

65) Differences between skeletal muscle cells and typical cells include which of the following? A) Skeletal muscle cells are larger than normal cells. B) Skeletal muscle cells are multinucleate. C) Skeletal muscle cells have one nucleus and typical cells have more than one. D) both A and B E) both A and C

D) both A and B

95) Muscle tissue that is involuntary: A) cardiac muscle only B) smooth muscle only C) skeletal muscle only D) cardiac muscle and smooth muscle E) cardiac muscle and skeletal muscle

D) cardiac muscle and smooth muscle

58) which of the following is *false* A) cardiac muscle contraction cannot be summated B) skeletal muscle contraction may be summated C) skeletal muscle control is neural D) cardiac muscle control is neural *only* E) Cardiocytes are interconnected through intercalated discs

D) cardiac muscle control is neural *Only*

83) Each of the following factors would increase the probability of skeletal muscles contracting, *EXCEPT* A) increased permeability of the muscle membrane to calcium ions B) increased amounts of acetylcholine in the synaptic cleft C) increased permeability of the muscle membrane to sodium ion D) increased permeability of the muscle membrane to potassium ion E) increased numbers of acetylcholine receptors at the motor end plate

D) increased permeability of the muscle membrane to potassium ion *(Sodium for Contraction)*

An Enlargement of the stimulated muscle

Hypertrophy

Length remains Constant while muscle Tension Changes

Isometric Contraction (Iso = Same; Metric = Length) (Isometric = Same Length)

Tension remains Constant while muscle Length Changes

Isotonic Contraction (Iso = Same ; Tonic = Tension) (Isotonic = Same Tension)