chap 10- muscle tissue and organization mc Flashcards
Which are considered specific characteristics of all muscle cells?
a: Contractility
b: Extensibility
c: Excitability
d: Elasticity
e: Conductivity
E. a, b, c, d, e
Which are possible functions of skeletal muscles?
a: Maintenance of posture
b: Both highly coordinated and localized simple movements
c: Temperature regulation
d: Support of certain body organs
e: Restricting the movement of material through certain body tracts
A. a, b, e
B. a, b, c
C. a, b, c, e
D. a, b, c, d
E. a, b, c, d, e
E. a, b, c, d, e
- In general, a skeletal muscle is composed of
a: Connective tissue sheaths
b: Nerves
c: Arteries
d: Veins
e: Muscle fibers
A. a, b, c, e
B. a, b, d, e
C. b, c, d, e
D. a, b, c, d
E. a, b, c, d, e
E. a, b, c, d, e
- Which is a correct listing of the hierarchy of a skeletal muscle’s components, beginning with the
smallest?
a: Myofibrils
b: Muscle fiber
c: Fascicle
d: Skeletal muscle
A. a, b, c, d
B. a, c, b, d
C. d, c, b, a
D. c, b, a, d
E. b, c, a, d
A. a, b, c, d
5.
Which is the correct order of the connective tissue layers of a skeletal muscle, beginning with the most superficial?
a: Endomysium
b: Epimysium
c: Perimysium
A. a, b, c
B. b, a, c
C. c, a, b
D. b, c, a
E. c, b, a
D. b, c, a
- The structure responsible for attaching muscle to bone is a
A. sphincter.
B. ligament.
C. fascia.
D. tendon.
E. myofibril.
D. tendon.
- The neurons that stimulate muscle contraction are called _____ neurons.
A. sensory
B. contractile
C. inhibitory
D.somatic motor
E. association
D.somatic motor
- The multiple nuclei in skeletal muscle cells are the result of the
A. fusion of myoblasts.
B. cytokinesis of embryonic satellite cells.
C. spontaneous development of nuclei in embryonic cells.
D. stimulation of fibroblasts by hormones.
E. action of testosterone on mesenchyme cell.
A. fusion of myoblasts.
- Which protein makes up the thick filaments?
A. Myosin
B. Actin
C. Tropomyosin
D. Troponin
E. Myopathy
A. Myosin
- What is the letter associated with the dark bands in a sarcomere?
A. I
B. A
C. Z
D. M
E. H
B. A
11.
In a sarcomere, which letter is associated with the thin dark line in the middle of an I band?
A. A
B. Z
C. M
D. H
B. Z
12.
In a sarcomere, which letter is associated with a region within the A band that is more lightly shaded because only thick filaments are
present?
A. I
B. A
C. M
D. Z
E. H
E. H
13.
In a sarcomere, which letter is associated with the light band that contains thin filaments only?
A. I
B. A
C. M
D. Z
E. H
A. I
14.
A sarcomere is defined as the distance from one _____ to the next.
A. Z disc
B. I band
C. H zone
D. A band
E. M line
A. Z disc
- Which is not a protein found in thin filaments?
A. Actin
B. Troponin
C. Tropomyosin
D.
Myosin
E. No exceptions; all are found in thin filaments.
D.
Myosin
- Which incorrectly describes what happens during skeletal muscle contraction?
A. The width of the A band remains constant.
B. The H zone disappears.
C. The Z discs of a sarcomere move farther apart.
D. The sarcomere narrows.
E. The I bands narrow.
C. The Z discs of a sarcomere move farther apart.
- The narrow space that separates the motor neuron and the skeletal muscle fiber in a neuromuscular
junction is called the
A. motor end plate.
B. synaptic vesicle.
C. synaptic cleft.
D. synaptic knob.
C. synaptic cleft.
- Which structures are reservoirs that store acetylcholine?
A. Synaptic vesicles
B. Synaptic clefts
C. Terminal cisternae
D. Lysosomes
E. Sarcomeres
A. Synaptic vesicles
- Which are the reservoirs that store the calcium required for muscle contraction?
A. Synaptic vesicles
B. Synaptic clefts
C. Terminal cisternae
D. Peroxisomes
E. Mitochondria
C. Terminal cisternae
- The calcium ions involved in skeletal muscle contraction bind to a(n)______ subunit.
A. myosin
B. actin
C. elastin
D. tropomyosin
E. troponin
E. troponin
- Which of the myofilaments of a muscle fiber has the active sites to which the heads of the thick
filaments will bind?
A. Actin
B. Troponin
C. Tropomyosin
D. Myosin
E.
Thick filament
A. Actin
- Which sequence correctly lists the changes that allow the thick and thin filaments to slide past one
another in skeletal muscle contraction?
A. Attach - pivot - detach - return
B. Pivot - attach - return - detach
C. Attach - detach - pivot - return
D. Return - pivot - attach - detach
E. Pivot - attach - detach - return
A. Attach - pivot - detach - return
- Which is the neurotransmitter that causes the release of calcium ions and initiates the steps of skeletal
muscle fiber contraction?
A. Acetylcholinesterase
B. Acetylcholine
C. Serotonin
D. Norepinephrine
B. Acetylcholine
- A motor unit consists of
a: A single motor neuron
b: Neuromuscular junctions
c: Muscle fibers
d: Several motor neurons
e: A single muscle fiber
A. a, b, e
B. a, b, c
C. b, c, d
D. a, e
E. c, d
B. a, b, c
- When muscle tension is greater than the resistance (weight), movement ______ occur.
A. will
B. will not
A. will
- When a muscle is isometrically contracted, its length _______ change.
A. does
B. does not
B. does not
- Which contraction occurs when you try (unsuccessfully) to move a wall?
A. Isometric
B. Isotonic
A. Isometric
- Which may occur as a result of muscle atrophy?
A. Muscle size is reduced.
B. Fibers become weaker.
C. Muscle loses tone.
D. Fibers waste away and die.
E. All of the choices are correct.
E. All of the choices are correct.
- The resistance to fatigue of fast fibers is ______ when compared to that of slow or intermediate
fibers.
A. low
B. high
C. identical
A. low
- The type of fibers specialized to continue contracting for extended periods of time, as would be
required in running a marathon, for example, are _____ fibers.
A. fast
B. slow
C. intermediate
D. fast and intermediate
E. slow and intermediate
B. slow
- The vascular supply to slow muscle fibers is ______ the network of capillaries around fast muscle
fibers.
A. more extensive than
B. less extensive than
C. the same as that of
A. more extensive than
- Which fibers dominate many of the back and calf muscles that contract almost continually to
maintain posture?
A. Slow
B. Fast
C. Intermediate
A. Slow
- The top long distance runners probably have _______ proportion of slow muscle fibers in their leg
muscles.
A. a higher
B. a lower
C. the same
A. a higher
- The majority of skeletal muscle fibers in the body are _____ fibers.
A. slow
B. fast
C. intermediate
B. fast
- A sphincter has
A. widespread muscle fibers that converge on a common attachment site.
B. muscle fibers concentrically arranged.
C. fibers arranged in a parallel form.
D. fascicles arranged obliquely to their tendon.
E. fascicles that alternate superiorly and inferiorly.
B. muscle fibers concentrically arranged.
- Pennate muscles resemble a
A. triangle.
B. leaf.
C. spindle.
D. feather.
E. strap.
D. feather.
- The most common type of pennate muscle configuration is
A. unipennate.
B. bipennate.
C. multipennate.
B. bipennate.
- The biceps brachii is an example of a ________ muscle.
A. bipennate
B. parallel
C. circular
D. convergent
E. multipennate
B. parallel
- The type of lever with the fulcrum in the middle is a ________ lever.
A. first-class
B. second-class
C. third-class
A. first-class
- When the force is applied between the resistance and the fulcrum, the result is a _____ lever.
A. first-class
B. second-class
C. third-class
C. third-class
- Using the mandible to close your mouth as you bite on food is an example of a _________ lever.
A. first-class
B. second-class
C. third-class
C. third-class
- When the muscles on the posterior side of the head pull on the skull and oppose the tendency of the
head to tip anteriorly, one has an example of a _____ lever.
A. first-class
B. second-class
C. third-class
A. first-class
- Which applies to synergist muscles?
a: Assist the agonist
b: Assist the antagonist
c: May stabilize the point of origin
d: May contribute to tension at the insertion site
e: Most useful at the end of a movement
A. a, c, d, e
B. b, c, d, e
C. a, c, d
D. b, c, e
E. b, c, d
C. a, c, d
- A muscle whose name has “profundus” in it is located
A. on the front.
B. deep.
C. on the side.
D. parallel to the midline.
E. superficially.
B. deep.
- In which body region would you expect to find a muscle whose name includes the word “pollicis”?
A. Great toe
B. Buttocks
C. Thumb
D. Neck
E. Wrist
C. Thumb
- A muscle whose name has “orbicularis” in it is _______ in appearance.
A. oblique
B. straight
C. small
D. very large
E. circular
E. circular
- A muscle whose name has “triceps” in it
A. has two muscle heads or tendons of origin.
B. has three muscle heads or tendons of origin.
C. has four sets of two muscle heads or tendons of origin.
D. has four muscle heads or tendons of origin.
E. is part of a complex of three separate muscles that rotate at a joint.
B. has three muscle heads or tendons of origin.
- The type of muscle fibers that are striated, form Y-shaped branches, and have junctions called
intercalated discs are
A. skeletal.
B. cardiac.
C. smooth.
D. voluntary.
E. skeletal and voluntary.
B. cardiac.
- The type of muscle fibers that have only a single nucleus, both thick and thin filaments, but no Z
discs, are
A. skeletal.
B. cardiac.
C. smooth.
D. cardiac and smooth.
E. cardiac and skeletal.
C. smooth.
- With increased age, skeletal muscles show
A. a decrease in the number of myofibrils.
B. an increase in muscle fiber diameter.
C. no change in oxygen storage capability.
D. increased glycogen reserves.
E. a tendency to fatigue less rapidly.
A. a decrease in the number of myofibrils.
- A term that could be used to describe the changes that occur in muscle fibers as humans age would be
A. proliferation.
B. hypertrophy.
C. convergence.
D. atrophy.
E. myofascia.
D. atrophy.
- Which region of a somite differentiates into the skeletal muscles?
A. Sclerotome
B. Dermatome
C. Myotome
C. Myotome
- This sarcomere depicts relaxed muscle. The M line is noted by number
A. 1.
B. 2.
C. 3.
D. 4.
E. 5.
D. 4.
