The pharyngeal phase of swallowing:

Correct Answer: C

Rationale: The correct answer is C because the pharyngeal phase of swallowing involves the peristaltic activity of the upper third of the esophagus, pushing the food bolus towards the stomach. This phase is involuntary and is controlled by the swallowing reflex. Choices A, B, and D are incorrect because the pharyngeal phase is entirely involuntary, the upper esophageal sphincter opens during the esophageal phase, and the opening of the glottis is associated with protection of the airway during swallowing, not the pharyngeal phase.

Correct Answer: B

Rationale: The migrating motor complex (MMC) functions to clear non-digestible material from the stomach and small intestine during fasting periods. Step 1: During fasting, MMC promotes gastrointestinal motility to prevent bacterial overgrowth. Step 2: MMC consists of 3 phases - quiescent, irregular contractions, and intense contractions - aiding in sweeping undigested materials. Step 3: This process helps maintain gut health and prevents issues like bacterial overgrowth or malabsorption. Summary: Choices A, C, and D are incorrect as they do not accurately describe the specific function of the migrating motor complex during fasting.

Correct Answer: C

Rationale: The correct answer is C: both. Occult fecal blood can indicate bleeding anywhere along the gastrointestinal tract. Upper gastrointestinal bleeding typically presents as melena (black, tarry stools), while lower gastrointestinal bleeding can manifest as occult blood in the stool. Therefore, occult fecal blood can be an indication of both upper and lower gastrointestinal bleeding. Choices A and B are incorrect because occult fecal blood is not exclusive to either upper or lower gastrointestinal bleeding alone. Choice D is incorrect since occult fecal blood can indeed be an indication of gastrointestinal bleeding.

Correct Answer: A

Rationale: The correct answer is A: Hemolytic jaundice is caused by more fragile RBCs. When red blood cells are destroyed at an increased rate, it leads to the release of more bilirubin, causing jaundice. Choice B is incorrect because liver damage leads to hepatocellular jaundice, not hemolytic. Choice C is incorrect as hemolytic jaundice is characterized by high bilirubin levels in the blood, not low levels in urine. Choice D is incorrect as option A is the correct explanation for hemolytic jaundice.

Correct Answer: D

Rationale: The correct answer is D because bile pigments, such as bilirubin, increase in the blood in liver disease due to impaired liver function. Bilirubin is a waste product from the breakdown of red blood cells and is normally processed by the liver. Elevated levels of bile pigments in the blood are a common indicator of liver dysfunction. Choice A is incorrect because bile pigments are derived from heme, not the globin portion of hemoglobin. Choice B is incorrect because bile pigments aid in the emulsification of fats but do not directly help in fat digestion and absorption. Choice C is incorrect as bile pigments are conjugated with glucuronic acid, not sulphate, in the liver.