Explain why the ratio of motor neurons to muscle fibers is greater in muscles that control eye movement than in postural muscles of the leg.
What will be an ideal response?
Answer: A motor unit is composed of a single motor neuron and all of the muscle fibers it controls. The movements of an eye require very precise control thus, each motor unit must be small. In contrast, there is much less precision of movement needed in the postural muscles of the leg, so one motor neuron will innervate many more muscle fibers
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A. ion. B. hydrophilic protein. C. large protein. D. hydrophilic carbohydrate. E. lipid/steroid.
The term systole means
a. closure b. conduction c. contraction d. opening e. relaxation
Which of the following will increase GFR?
1.Vasodilation of afferent arteriole 2.Sympathetic stimulation 3.Decrease in glomerular hydrostatic pressure 4.Decrease in net filtration pressure
Which nerves innervate most of the muscles of facial expression?
A. The facial nerves (CN VII) B. The vagus nerves (CN X) C. The first pair of spinal nerves D. The glossopharyngeal nerves (CN IX) E. The trigeminal nerves (CN V)