Why does the superior part of the esophagus contain skeletal muscle instead of smooth muscle?
A. The second phase of swallowing is under involuntary control.
B. The first phase of swallowing is under voluntary control.
C. The second phase of swallowing is under voluntary control.
D. The first phase of swallowing is under involuntary control.
Answer: B
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The branches that arise from the celiac trunk are the
A. left gastric and splenic arteries. B. left gastric, left gastroepiploic, and splenic arteries. C. left gastroepiploic and splenic arteries. D. left gastric, splenic, and common hepatic arteries. E. left gastric and common hepatic arteries.
Which channel type is sensitive to serotonin?
a. voltage-gated b. chemically-gated c. mechanically-gated d. acoustically-gated e. none of these
The exact causes of inflammatory bowel diseases continue to be explored, but it is relatively clear that
A. the cause is allergy to a single particular food, and patients get immediate relief by simply not eating that food. B. individuals suffering from its effects are largely experiencing the consequences of the absence of immune mechanisms in the gastrointestinal tract. C. it can be easily diagnosed since its symptoms are always very specific and the affected areas are always limited to a very focused area within the small intestine. D. it is likely to result from a combination of environmental and genetic factors. E. it is equally common among people of all ages and racial groups within the population.
By the end of gestation, maternal blood volume normally increases by almost ________ percent
A) 20 B) 25 C) 50 D) 80 E) 100