BIO 251 - Unit Exam 4. Questions with Answers. A+ Guide.

BIO 251 - Unit Exam 4. Questions with Answers. A+ Guide. Question 1 of 22 4.0/ 4.0 Points The stomach is protected from self-digestion by the ______________. When this breaks down, _________ can form and be painful.  A. Muscularis mucosa; nodules  B. Mucosal barrier; ulcers  C. Duodenum; ulcers  D. Serosa; nodules  E. None of the above is correct Feedback: Good work; your answer is correct! Question 2 of 22 4.0/ 4.0 Points The ___________ is the thin layer of the mucosa responsible for pulling the mucosa into its many folds which increases the surface area of the alimentary canal.  A. Muscularis (externa)  B. Submucosa  C. Serosa  D. Muscularis mucosa  E. None of the above Feedback: Good work; your answer is correct! Question 3 of 22 4.0/ 4.0 Points Where are carbohydrates first digested? 