ATI LPN
Chapter 15 The Gastrointestinal System Review Questions Questions
Question 1 of 5
The whitish tips of filiform papillae consist of:
Correct Answer: A
Rationale: The correct answer is A: keratinized epithelial tissue. Filiform papillae are composed of keratinized epithelial cells that form the whitish tips on the surface of the tongue. These cells are designed to provide a rough surface to help with food manipulation. Collagen (B) is a structural protein found in connective tissue, not in filiform papillae. Mucous (C) is a secretion produced by mucous glands and is not a component of filiform papillae. Taste buds (D) are specialized structures responsible for detecting taste, located in fungiform and circumvallate papillae, not in filiform papillae.
Question 2 of 5
Which of the following epithelial types is most closely associated with passive protection, without specialization for either secretion or absorption, as in the esophagus and anal canal?
Correct Answer: B
Rationale: The correct answer is B: stratified squamous. The esophagus and anal canal are exposed to mechanical stress and abrasion, requiring a protective epithelium. Stratified squamous epithelium is ideal for this role due to its multiple layers of cells that provide durability and protection against wear and tear. Simple squamous epithelium (choice A) is too thin and fragile for this function. Simple columnar epithelium (choice C) is specialized for secretion and absorption, not for protection. Stratified columnar epithelium (choice D) is relatively rare in the body and not typically found in areas requiring high protection like the esophagus and anal canal.
Question 3 of 5
Which of the following regions of the GI tract is characterized by permanent folds (plica)?
Correct Answer: C
Rationale: The correct answer is C: small intestine. The small intestine is characterized by permanent folds called plicae circulares, which increase the surface area for nutrient absorption. These folds help to slow down the passage of food and increase contact with the intestinal walls. The other choices are incorrect because the esophagus (A) does not have permanent folds, the stomach (B) has rugae (temporary folds), and the large intestine (D) has haustra (pouches), not permanent folds like the small intestine.
Question 4 of 5
Tissue from which of the following is often poorly preserved in autopsy specimens, because it self-destructs soon after death due to post-mortem release of its stored secretory product of proteolytic enzymes?
Correct Answer: D
Rationale: The correct answer is D: pancreas. Pancreatic tissue is often poorly preserved in autopsy specimens due to the post-mortem release of its stored secretory product, which is a highly concentrated mixture of proteolytic enzymes. These enzymes can rapidly degrade the pancreatic tissue itself, leading to self-destruction soon after death. This phenomenon is known as autolysis. Submaxillary and sublingual glands (choice A), esophageal glands (choice B), and duodenal (Brunner's) glands (choice C) do not typically release such high concentrations of proteolytic enzymes upon death, leading to better preservation in autopsy specimens compared to pancreatic tissue.
Question 5 of 5
Which of the dimensions is about 1-2 millimeters?
Correct Answer: A
Rationale: The correct answer is A. The thickness of the stomach wall (all layers) is about 1-2 millimeters. This includes the mucosa, submucosa, muscularis, and serosa layers, which together make up the entire thickness of the stomach wall. The other choices are incorrect because: B. The thickness of the gastric mucosa is much thinner than 1-2 millimeters. C. The height of the stomach's surface epithelial cells is a microscopic measurement, not in the millimeter range. D. The diameter of a parietal cell is also a microscopic measurement, not in the millimeter range. Therefore, the correct answer is A based on the actual dimensions of the structures mentioned in the question.