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2011-04-30 19:03:33

Muscle Tissue and Organization
Show Answers:

  1. Individual skeletal muscle cells are known as
    muscle fibers
  2. All of the following are functions of skeletal muscle tissue except
    cooling of the body
  3. The three types of muscle tissue are
    skeletal, cardiac, and smooth
  4. The layer of dense irregular connective tissue that surrounds the entire
    skeletal muscle is the
  5. What is the cell membrane of a muscle fiber called?
  6. Each of the following is an attribute of skeletal muscle fibers except
    lack striations
  7. A thick, fibrous connective tissue cord that attaches a muscle to a bone is
    a tendon
  8. What are the principal proteins of muscle contraction?
    actin and myosin
  9. Which structures extend into the sarcoplasm as a network of deep invaginations
    of the sarcolemma?
    transverse tubules
  10. The functional contractile units of a skeletal muscle fiber are the
  11. A nerve impulse triggers the release of what chemical at a neuromuscular
    acetylcholine (ACh)
  12. Which term describes the expanded tip of an axon at a neuromuscular junction?
    synaptic knob
  13. Which part of a sarcomere contains entire thick filaments and lateral end
    regions with overlapping thin filaments?
    A band
  14. When a muscle fiber contracts, what slides toward the center of each sarcomere?
    the thin filaments of actin
  15. A reduction in muscle size, tone, and power is called
  16. A muscle impulse travels deep into the muscle fiber along
    T-tubule membranes
  17. A single motor neuron, the muscle fibers it controls, and the neuromuscular
    junctions in between constitute a
    motor unit
  18. When stimulated by a muscle impulse, what do the terminal cisternae release into
    the sarcoplasm?
    calcium ions, Ca2+
  19. The arrangement of tendons and fascicles in a ____________ muscle resembles the
    structure of a feather.
  20. Types of skeletal muscle fibers include
    • fast
    • intermediate
    • slow
    • all of the above
  21. Muscle fibers are arranged concentrically in
    circular muscles
  22. Types of pennate muscles include which of the following?
    • multipennate
    • bipennate
    • unipennate
    • all of the above
  23. Attributes of a convergent muscle include all of the following except
    fascicles insert obliquely onto a tendon extending through the muscle
  24. The most common levers in the body are ____________ levers
  25. Most muscles are attached at one end to a less movable point known as the
    it is the main muscle that contracts to produce a particular movement
  26. Which of the following describes a first-class lever
    the fulcrum is situated between the force and the resistance
  27. All of the following characteristics are used in naming muscles except
  28. The deltoid muscle is named on the basis of its
  29. Of the following terms used in muscle names, which one refers to a specific body
  30. Which of the following characterizes both skeletal and smooth muscle
  31. The "muscular system" includes muscles in which of these locations?
    surrounding the orbit
  32. How do skeletal muscle fibers get multiple nuclei?
    fusion of embryonic myoblasts
  33. In skeletal muscle fibers, where do calcium ions occur at varying concentrations?
    • in the terminal cisternae of the sarcoplasmic reticulum
    • throughout the sarcoplasm
    • in regions where the thin and thick filaments overlap
    • all of the above
  34. In what order would a scalpel first penetrate these layers of connective tissue
    upon cutting into the biceps brachii muscle: (1) endomysium (2) epimysium (3)
    2, 3, 1
  35. Which list of muscle structures proceeds from smaller to larger in diameter?
    myofilament, myofibril, muscle fiber, fascicle
  36. What are satellite cells?
    unfused myoblasts
  37. Blood vessels and nerve fibers that supply skeletal muscle fibers must penetrate
    epimysium, perimysium, and endomysium
  38. Synaptic knobs are to axons as ____________ are to
    sarcolemmae, in that both are structural modifications involved in
    transmitting electrochemical signals across the synaptic cleft.
    motor end plates
  39. Skeletal muscle contraction involves which of the following events?
    • a nerve impulse followed by a muscle impulse
    • release of calcium ions from terminal cisternae
    • tropomyosin moving to expose active sites on actin molecules
    • all of the above
  40. Of the following, which is the first to occur during muscle contraction?
    crossbridges link thick and thin filaments

  41. In the sliding
    filament mechanism, crossbridges are
    myosin heads that bind to active sites on a thin filament

  42. Interactions
    between thick and thin filaments during muscle contraction occur in which
    attach, pivot, detach, return

  43. What actually
    shortens when a muscle fiber contracts?
    sarcomeres, H zones, and I bands

  44. How many motor
    end plates does a typical skeletal muscle fiber contain?
    only one

  45. Rigor mortis
    demonstrates that skeletal muscle tissue
    • normally requires energy to end as well as to start a contraction
    • can survive and function for some time after the heart stops beating
    • maintains powerful contractions even with no ATP, until autolysis occurs
    • all of the above

  46. For any given
    muscle, the total force exerted by a contraction depends on
    the number of activated motor units

  47. Physical
    conditioning can effectively decrease the proportion of which type of
    muscle fibers?

  48. Reflecting
    their different needs, fast muscle fibers contain large ____________ reserves
    whereas slow fibers contain the oxygen-carrying pigment ____________.
    glycogen; myoglobin

  49. An overdose of
    cholinesterase inhibitors could produce effects most similar to those of

  50. Among the
    patterns of fascicle arrangements, ____________ muscles can move their tendons
    farther but ____________ muscles of the same size are stronger.
    parallel; pennate

  51. In the limbs,
    the insertion of a muscle typically lies
    distal to the origin

  52. In terms of
    ability to produce ATP, cardiac muscle fibers are most like
    slow skeletal muscle fibers

  53. Z discs
    are to skeletal muscle as ____________ are to smooth muscle.
    dense bodies

  54. Aging affects
    the muscular system in all of the following ways except
    decrease in amount of connective tissue within muscles
  55. The unit of muscle structure that is composed of bundles of myofibrils, enclosed
    within a sarcolemma, and surrounded by a connective tissue covering called
    endomysium is a
    muscle fiber.

  56. During the
    contraction of a muscle fiber, myofibrils

  57. In a convergent
    muscle, the fibers are
    widespread over a broad area and joined at a common attachment site.

  58. The plasma
    membrane of a skeletal muscle fiber is called the

  59. In a skeletal
    muscle fiber, a triad is composed of
    one transverse tubule and two terminal cisternae.

  60. During
    development, the ___ of a somite gives rise to skeletal muscle.

  61. What is a
    synaptic knob?

  62. The muscle that
    assists the prime mover is called the

  63. Which of the
    following changes in skeletal muscles is associated with aging?
    Muscle fibers increase in diameter.