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Question
Why does the upper third of the esophagus have skeletal muscle in its wall?
A. so you do not choke
B. the first phase of swallowing is voluntary
C. so that peristalsis can occur
D. the first phase of swallowing is involuntary
Answer
This answer is hidden. It contains 10 characters.
Related questions
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arteries
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C. osteocytes.
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