A patient who has chronic constipation asks the nurse about the use of psyllium (Metamucil). Which information will the nurse include in the response?

Correct Answer: D

Rationale: Rationale for Correct Answer D: - Psyllium is a bulk-forming laxative that works by absorbing water in the intestines, forming a gel-like mass that helps with bowel movements. - Taking large amounts of fluid is essential when using psyllium to prevent the gel-like mass from hardening and causing impaction or bowel obstruction. - Adequate fluid intake is crucial for the safe and effective use of psyllium as a laxative. Summary of Incorrect Choices: - Choice A is incorrect because fiber-containing laxatives like psyllium do not directly impact the absorption of fat-soluble vitamins. - Choice B is incorrect as dietary sources of fiber should not be eliminated entirely but rather balanced to prevent excessive gas. - Choice C is incorrect as all medications, including laxatives, can have potential adverse effects; however, psyllium is generally well-tolerated when used appropriately.

Correct Answer: B

Rationale: The correct answer is B: pyloric valve. The pyloric valve is located between the stomach and the small intestine, specifically at the junction of the stomach and the duodenum. Its main function is to regulate the flow of partially digested food from the stomach into the small intestine. This control is crucial to ensure that the small intestine receives food at a manageable rate for optimal digestion and absorption of nutrients. The cardiac sphincter (A) is located at the entrance of the stomach from the esophagus and prevents acid reflux. The ileo-colic valve (C) is located between the small and large intestines, controlling the flow of contents between them. The sphincter of Oddi (D) regulates the flow of bile and pancreatic juice into the small intestine.

Correct Answer: B

Rationale: The falciform ligament separates the right and left lobes of the liver. This is because it attaches the liver to the anterior abdominal wall and suspends it from the diaphragm, dividing the liver into right and left lobes. The quadrate, caudate, and pancreatic lobes are not separated by the falciform ligament, making choices A, C, and D incorrect, respectively.

Correct Answer: C

Rationale: The correct answer is C: jejunum. The jejunum is the middle part of the small intestine where the majority of nutrient absorption takes place. Its large surface area, due to the presence of villi and microvilli, facilitates efficient absorption of nutrients. The duodenum (B) primarily aids in digestion, not absorption. The ileum (D) absorbs bile salts and vitamin B12, but most nutrient absorption occurs in the jejunum. The colon (A) primarily absorbs water and electrolytes, not nutrients. Therefore, the jejunum is the correct answer for the site of most nutrient absorption in the digestive system.

Correct Answer: D

Rationale: Carboxypeptidase is a metalloenzyme that requires zinc (Zn) for its activity as a cofactor. Zinc plays a crucial role in stabilizing the enzyme's structure and facilitating the catalytic reaction. Copper (A), niacin (B), and iron (C) are not directly involved in the enzymatic activity of carboxypeptidase. Copper is more commonly associated with other enzymes like cytochrome c oxidase, niacin is a vitamin, and iron is typically involved in heme-containing proteins like hemoglobin. Zinc is the correct choice as it directly supports carboxypeptidase function.