Page 327 - Atlas of Histology with Functional Correlations
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E. T tubules in skeletal muscle are located over the Z lines.
2. Calcium is essential for muscle contraction. In cardiac muscles, calcium
ions enter the sarcomere from:
A. the sarcoplasmic reticulum cisternae.
B. T tubules and sarcoplasmic storage sites.
C. outside of the muscle fibers and from the sarcoplasmic reticulum.
D. interstitial fluid outside of the muscle fibers and the T tubules.
E. T tubules and the triads.
3. The dense bodies of the smooth muscle are similar to:
A. Z lines in the striated muscles.
B. myosin myofilaments.
C. actin myofilaments.
D. T tubules and the sarcoplasmic reticulum.
E. T tubules and triads.
4. The caveolae in the smooth muscle are located in the:
A. dense bodies.
B. actin and myosin myofilaments.
C. cisternae of the sarcoplasmic reticulum.
D. sarcoplasm (cell interior).
E. cell membrane.
5. The caveolae in smooth muscle perform what function?
A. They bind calcium in the sarcoplasm.
B. They attach to actin and myosin during smooth muscle contraction.
C. They control the influx of calcium into the smooth muscle fibers.
D. They conduct stimulatory impulses to the dense bodies.
E. They transmit contracting force to neighboring cells.
ANSWERS
1. Correct Answer: B. T tubules are larger and store more calcium in skeletal
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