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| 1 | |
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 |
| | A) | myofibril. |
| | B) | fascicle. |
| | C) | myofilament. |
| | D) | muscle fiber. |
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| 2 | |
During the contraction of a muscle fiber, myofibrils |
| | A) | lengthen. |
| | B) | remain unchanged. |
| | C) | increase in diameter. |
| | D) | shorten. |
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| 3 | |
In a convergent muscle, the fibers are |
| | A) | oblique to the tendon of the muscle. |
| | B) | concentrically arranged. |
| | C) | parallel to the long axis of the muscle. |
| | D) | widespread over a broad area and joined at a common attachment site. |
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| 4 | |
The plasma membrane of a skeletal muscle fiber is called the |
| | A) | sarcoplasmic reticulum. |
| | B) | sarcolemma. |
| | C) | sarcoplasm. |
| | D) | sarcomysium. |
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| 5 | |
In a skeletal muscle fiber, a triad is composed of |
| | A) | myosin, actin, and myofibrils. |
| | B) | one A band, one H zone, and one I band. |
| | C) | one transverse tubule and two terminal cisternae. |
| | D) | myofilaments, myofibrils, and sarcomeres. |
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| 6 | |
During development, the ___ of a somite gives rise to skeletal muscle. |
| | A) | dermatome |
| | B) | scleroblast |
| | C) | myotome |
| | D) | satellite cell |
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| 7 | |
What is a synaptic knob? |
| | A) | receptor for neurotransmitter in the neuromuscular junction |
| | B) | membrane sac holding the neurotransmitter |
| | C) | expanded tip of an axon at the neuromuscular junction |
| | D) | the space that separates the neuron from the muscle fiber |
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| 8 | |
The bundle of dense regular connective tissue that attaches a skeletal muscle to bone is called a(n) |
| | A) | tendon. |
| | B) | ligament. |
| | C) | endomysium. |
| | D) | fascicle. |
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| 9 | |
The muscle that assists the prime mover is called the |
| | A) | antagonist. |
| | B) | synergist. |
| | C) | agonist. |
| | D) | None of these are correct. |
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| 10 | |
Which of the following changes in skeletal muscles is associated with aging? |
| | A) | Muscle fibers increase in diameter. |
| | B) | Muscles become more elastic. |
| | C) | Muscle fibers increase their glycogen reserves. |
| | D) | The number of satellite cells in muscle decreases. |
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