Which of these cells secrete hormones?

Correct Answer: C

Rationale: The correct answer is C: enteroendocrine cells. These cells are specialized in secreting hormones in the gastrointestinal tract, regulating various physiological processes. Parietal cells secrete hydrochloric acid, mucous neck cells produce mucus for protection, and chief cells secrete pepsinogen for protein digestion. Therefore, enteroendocrine cells are the only cells among the options responsible for hormone secretion in this context.

Correct Answer: C

Rationale: The correct answer is C: large intestine. The large intestine is responsible for absorbing the majority of water in the digestive system. This occurs in the colon, where water is reabsorbed from the indigestible food residue, turning it into solid waste. The stomach (A) primarily breaks down food, the small intestine (B) absorbs nutrients, and the rectum (D) stores feces before elimination. Therefore, the large intestine is the correct choice for water absorption in the digestive process.

Correct Answer: C

Rationale: The term 'chyme' refers to food mixed with digestive juices in the stomach. This mixture is the result of mechanical and chemical digestion processes. Choice A, undigested food, is incorrect as chyme is a product of digestion. Choice B, partially digested food, is not precise enough as chyme specifically refers to the semi-fluid mass in the stomach. Choice D, absorbed nutrients, is incorrect as chyme is not yet at the stage where nutrients are absorbed. Thus, choice C is correct as it accurately describes the composition of chyme in the digestive system.

Correct Answer: A

Rationale: Cholecystokinin (CCK) is released after a meal to stimulate the release of bile from the gallbladder into the small intestine to aid in digestion and absorption of fats. This process is crucial for emulsifying fats and enhancing their digestion. Choice A is correct because it directly aligns with the primary function of CCK. Choices B, C, and D are incorrect because CCK does not play a role in stimulating gastric acid secretion, insulin release, or absorption of nutrients. These functions are typically controlled by other hormones such as gastrin, insulin, and various enzymes in the digestive system.

Correct Answer: B

Rationale: The correct answer is B: Liver. The liver is an accessory digestive organ as it produces bile, which aids in the digestion and absorption of fats in the small intestine. The other choices, A: Esophagus, C: Stomach, and D: Small intestine, are primary digestive organs involved directly in the process of digestion and absorption of nutrients. The esophagus is responsible for transporting food to the stomach, the stomach digests food with gastric juices, and the small intestine is where most of the digestion and absorption of nutrients occur. Therefore, the liver stands out as the correct answer as it supports the digestive process rather than directly participating in it.