Skeletal Muscle I, II Flashcards
As fiber length increases:
A. Excursion of the muscle increases
B. Excursion of the muscle decreases
C. Excursion of the muscle does not change
A
The following image shows:
A. An H&E stain of longitudinal muscle fiber
B. A H&E stain of cross-sectional muscle fiber
C. A Mallory stain of collagen fibers
D. None of these/cannot tell from the information given
A
Which is true regarding myofibrils?
A. There are multiple muscle fibers in a single myofibril
B. They are described as a string of sacromeres
B
The cell membrane of he muscle fiber is:
A. The sacrolemma
B. The sacromere
C. The sacroplasmic reticulum
D. The myofibril
A
Which protein component of the sarcolemma links the extracellular matrix with the actin cytoskeleton?
A. Laminin
B. Hinges
C. alpha-Dystrobrevin
D. Dystrophin-associated protein complex (DAPC)
E. Sarcoglycans
D
Which of the following does not occur in skeletal muscle fiber?
A. Hypertrophy
B. Hyperplasia
C. Atrophy
D. All of these can occur in skeletal muscle fiber
B
Which disease is associated with Hypoexcitability of the ion channels?
A. Nondystrophic myotonia
B. Malignant hyperthermia
C. Andersen-Tawi Syndrome
D. More than one of these
C
Mutations in the sarcoglycan complex result in:
A. Duchenne muscular dystrophy
B. Becker muscular dystrophy
C. Limb-girdle muscular dystrophy
D. Congenital myopathy
E. Cardiomyopathy
C
Mutations in integrin alpha-7 result in:
A. Duchenne muscular dystrophy
B. Becker muscular dystrophy
C. Limb-girdle muscular dystrophy
D. Congenital myopathy
E. Cardiomyopathy
D
Mutations in the dystrophin protein can result in:
A. Duchenne muscular dystrophy
B. Becker muscular dystrophy
C. Cardiomyopathy
D. All of the above
D
What is the Triad of the sacroplasmic reticulum?
2 terminal cisternae and 1 t-tubule that play a central role in E-C coupling.
Malignant Hyperthermia:
A. Is treating by heat therapy
B. Is not a life-threatening condition
C. Is uncontrolled release of Ca2+ from the SR resulting in severe muscle contraction
D. Causes an anesthesia-induced drop in core BT and severe muscle rigidity
C
During contraction:
A. The actin filament moves the myosin filament towards the Z-disc
B. The myosin filament moves the actin filament towards the Z-disc
C. The actin filament moves the myosin filament towards the M-line
D. The myosin filament moves the actin filament towards the M-line
C
Titin:
A. is described “like a spring”
B. serves as the molecular ruler to specify thin filament length
C. has a carboxy terminal that attaches to the Z-line
D. all of these
E. none of these
A
