The nurse is caring for a patient who complains, "I don't see why I can't have a CT scan instead of the expensive MRI!" Which response is most appropriate for the nurse to make?

Correct Answer: A

Rationale: The correct answer is A because MRI provides better contrast between normal and pathologic tissue compared to CT scans. This is crucial for accurately diagnosing certain conditions. Choice B is incorrect as MRI images often require more complex analysis. Choice C is incorrect as both MRI and CT scans can produce digital images. Choice D is incorrect because CT scans expose patients to less radiation than MRI.

Correct Answer: C

Rationale: The main role of the stomach is the digestion of proteins. Step 1: Stomach secretes gastric juices containing pepsin and hydrochloric acid. Step 2: Proteins are broken down into peptides and amino acids. Step 3: These smaller molecules are then further digested and absorbed in the small intestine. Absorption of nutrients (A) primarily occurs in the small intestine, not the stomach. Bile is produced in the liver and stored in the gallbladder, not secreted by the stomach (B). The transport of food (D) occurs through the esophagus and into the stomach, not the main role of the stomach itself.

Correct Answer: C

Rationale: The correct answer is C: Secreting digestive enzymes. The pancreas secretes digestive enzymes such as amylase, lipase, and proteases to break down carbohydrates, fats, and proteins in the small intestine. This aids in digestion and absorption of nutrients. Producing insulin (Choice A) is a function of the pancreas but is primarily related to regulating blood sugar levels, not digestion. Producing bile (Choice B) is a function of the liver, not the pancreas. Absorbing nutrients (Choice D) is a function of the small intestine, not the pancreas. Therefore, the correct answer is C based on the role of the pancreas in digestion and enzyme secretion.

Correct Answer: D

Rationale: The correct answer is D, bile salts. The jejunum is primarily responsible for the absorption of nutrients like glucose, amino acids, and fatty acids. Bile salts are mainly absorbed in the ileum, the part of the small intestine that follows the jejunum. Bile salts aid in the digestion and absorption of fats, but they are not absorbed in the jejunum. Therefore, the jejunum is not the main site for absorption of bile salts. This makes option D the correct answer.

Correct Answer: D

Rationale: The correct answer is D because the pharyngeal phase of swallowing involves the contraction of the pharyngeal constrictors, which propel the bolus of food or liquid down the pharynx towards the esophagus. This muscular contraction helps in the proper movement of the swallow. A, a deep breath, is not part of the pharyngeal phase but may precede swallowing. B, elevation of the tongue against the hard palate, is part of the oral phase of swallowing, not the pharyngeal phase. C, contraction of the upper esophageal sphincter, occurs in the esophageal phase, not the pharyngeal phase.