BIOS256: Week 3 Exam 1 (Sept 2026)

BIOS256: Week 3 Exam 1 (Sept 2026)

                  BIOS256 Week 3 Exam 1
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Which of the following structures is part of the alimentary canal from the digestive system?
A. esophagus ✅
B. gallbladder
C. pancreas
D. liver
E. salivary glands
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Which region of the small intestine is primarily responsible for nutrient absorption?
A. jejunum ✅
B. pylorus
C. ileum
D. duodenum
E. sigmoid
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Which sphincter prevents regurgitation of stomach contents into the esophagus?
A. pyloric sphincter
B. lower esophageal sphincter ✅
C. internal anal sphincter
D. ileocecal valve
E. upper esophageal sphincter
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Arrange the following digestive organs in the correct order in which food passes through them.
Correct order: ✅
1. oral cavity
2. pharynx
3. esophagus
4. stomach
5. duodenum
6. jejunum
7. ileum
8. cecum
9. colon
10. rectum
11. anal canal

Which reflex is mediated by the enteric nervous system and initiates peristaltic waves in the rectum without spinal cord involvement?
A. vasovagal reflex
B. intrinsic defecation reflex ✅
C. parasympathetic reflex
D. cephalic reflex
E. enterogastric reflex

Which layer of the GI tract wall contains epithelial tissue specialized for secretion and absorption?
A. Muscularis externa
B. Submucosa
C. Serosa
D. Adventitia
E. Mucosa ✅