Exam | Portage Learning |Q&A | 26/27 Edition
(PDF)
1. Which of the following best defines the primary function of the liver?
A) To release insulin and glucagon for blood glucose regulation
B) To filter waste products from the blood and produce urine
C) To produce bile, metabolize nutrients, and synthesize plasma proteins
D) To secrete digestive enzymes into the small intestine
Correct Answer: To produce bile, metabolize nutrients, and synthesize plasma proteins
Rationale: The liver is a metabolic powerhouse responsible for bile production, carbohydrate and lipid
metabolism, protein synthesis (e.g., albumin, clotting factors), and detoxification. Insulin is secreted by
the pancreas, filtration and urine production are renal functions, and digestive enzymes are secreted by
the pancreas and intestinal glands.
2. What is the correct order of the four layers of the gastrointestinal wall, from innermost to outermost?
A) Serosa, muscularis externa, submucosa, mucosa
B) Mucosa, submucosa, muscularis externa, serosa
C) Submucosa, mucosa, serosa, muscularis externa
D) Muscularis externa, serosa, mucosa, submucosa
Correct Answer: Mucosa, submucosa, muscularis externa, serosa
Rationale: The GI wall consists of four concentric layers. From the lumen outward, they are the mucosa
(innermost), submucosa, muscularis externa, and serosa (outermost). This layered structure supports
the specialized functions of digestion, absorption, and motility.
3. What type of cell in the stomach is responsible for secreting hydrochloric acid (HCl)?
,A) Chief cells
B) G cells
C) Parietal cells
D) Mucous cells
Correct Answer: Parietal cells
Rationale: Parietal cells, located in the gastric glands of the stomach, secrete hydrochloric acid and
intrinsic factor. Chief cells secrete pepsinogen, G cells secrete gastrin, and mucous cells secrete
protective mucus.
4. The intermittent, wave-like contractions that mix and propel food along the gastrointestinal tract are
known as:
A) Segmentation
B) Peristalsis
C) Rhythmic movements
D) Haustration
Correct Answer: Rhythmic movements
Rationale: Rhythmic movements are the intermittent contractions that help mix and propel food along
the GI tract. Peristalsis is the coordinated, wave-like contraction that propels contents forward, while
segmentation is primarily a mixing movement.
5. What is the name of the double-layered fold of peritoneum that hangs down from the stomach to
adjacent organs?
A) Mesentery
B) Omentum
C) Falciform ligament
D) Greater ligament
, Correct Answer: Omentum
Rationale: The omentum is a double-layered fold of peritoneum that hangs down from the stomach and
covers the abdominal organs. The mesentery attaches the small intestine to the posterior abdominal
wall, and the falciform ligament attaches the liver to the anterior abdominal wall.
6. The submucosal plexus, also known as Meissner's plexus, is located between which layers of the
intestinal wall?
A) Mucosa and submucosa
B) Submucosa and muscularis externa
C) Muscularis externa and serosa
D) Within the mucosa itself
Correct Answer: Submucosa and muscularis externa
Rationale: Meissner's (submucosal) plexus lies between the mucosal and muscle layers of the intestinal
wall. It is involved in controlling secretions, absorption, and local contraction of each segment of the
intestinal tract. The myenteric (Auerbach's) plexus lies between the two muscle layers.
7. Which of the following GI hormones has strong growth hormone-releasing activity and stimulates
food intake?
A) Gastrin
B) Secretin
C) Ghrelin
D) Cholecystokinin (CCK)
Correct Answer: Ghrelin
Rationale: Ghrelin is a GI hormone with strong growth hormone-releasing activity that stimulates food
intake and digestive function. Gastrin stimulates gastric acid secretion, secretin stimulates pancreatic
bicarbonate secretion, and CCK stimulates gallbladder contraction and pancreatic enzyme secretion.