Which of these processes occurs in the mouth?

Correct Answer: D

Rationale: In the mouth, ingestion occurs when food is taken in. Mechanical digestion occurs through chewing and mixing food with saliva. Chemical digestion begins with enzymes in saliva breaking down carbohydrates. Therefore, all processes (ingestion, mechanical digestion, and chemical digestion) occur in the mouth. Other choices are incorrect because they do not encompass all the processes that happen in the mouth.

Correct Answer: B

Rationale: The correct answer is B: Metabolic acidosis. During bowel preparation for a colonoscopy, the patient may experience electrolyte imbalances due to fluid loss from diarrhea and bowel cleansing agents. This can lead to metabolic acidosis, characterized by low pH and bicarbonate levels in the blood. The nurse should monitor for signs such as confusion, weakness, and rapid breathing. Diarrhea (A) is a common side effect of bowel preparation but is not the most critical complication to monitor. Fatigue (C) and dyspnea (D) are not directly related to the electrolyte imbalances that can lead to metabolic acidosis in this scenario.

Correct Answer: C

Rationale: Peristalsis refers to the rhythmic contractions that move food along the digestive tract. This process helps propel food from the esophagus to the stomach and through the intestines for digestion and absorption. It is an involuntary movement controlled by the autonomic nervous system. Choice A is incorrect as it refers to digestion, not movement. Choice B is incorrect as peristalsis is involuntary, not voluntary. Choice D is incorrect as peristalsis does not involve absorption but rather transportation of food.

Correct Answer: A

Rationale: The small intestine is the correct answer because it is the primary site for nutrient absorption, including vitamins and minerals. It has a large surface area thanks to villi and microvilli, facilitating absorption. The large intestine mainly absorbs water and electrolytes, not vitamins and minerals. The mouth and esophagus are not involved in nutrient absorption but rather in the initial stages of digestion and transportation of food.

Correct Answer: A

Rationale: The correct answer is A: Villi. Villi are finger-like projections lining the small intestine that increase surface area for nutrient absorption. This structure is crucial for efficient digestion and absorption of nutrients. The other choices are incorrect because: B: Hepatic portal vein - This structure is not found in the small intestine but connects the intestines to the liver. C: Goblet cells - While present in the small intestine, they are not a defining structure of the small intestine. D: Mesenteries - These are connective tissues that support and hold organs in place, not a structure specific to the small intestine.