If no carbohydrate ingestion occurs in the body during a 24-hour period, liver activity provides for the body's needs by

Correct Answer: C

Rationale: The correct answer is C: converting glycogen into glucose. When no carbohydrate ingestion occurs, the liver breaks down stored glycogen into glucose through a process called glycogenolysis to maintain blood glucose levels. This process provides a source of energy for the body. Emulsification (A) is the breakdown of fats into smaller droplets, not related to carbohydrate breakdown. Manufacturing more bile (B) is not directly related to liver activity in response to no carbohydrate ingestion. Releasing iron (D) is unrelated to the liver's response to carbohydrate deprivation.

Correct Answer: B

Rationale: The correct answer is B: an ulcer. In the cartoon, the 'festering' pit indicates a hole or erosion in the stomach lining, which is characteristic of an ulcer. Ulcers are sores that form in the stomach or small intestine due to factors like bacterial infection or excessive acid production. Gallstones (A) are solid particles that form in the gallbladder, not in the stomach. Appendicitis (C) is inflammation of the appendix, not related to stomach issues. A goiter (D) is an enlargement of the thyroid gland, not linked to stomach ulcers. The 'festering' pit aligns with the symptoms and location of an ulcer, making it the most likely disorder represented.

Correct Answer: C

Rationale: The correct answer is C: Decreased urine production allows the body to conserve water. When an athlete sweats a lot during a long-distance run on a hot day, the body loses water through sweat. To prevent dehydration, the kidneys reduce urine production, allowing the body to retain more water. This helps maintain proper hydration levels and prevent water loss. Rationale: A: Decreased urine production does not directly impact amino acids in the blood. Amino acids are primarily regulated by protein metabolism and dietary intake. B: Increased urine production does not specifically target the removal of amino acids produced during exercise. Amino acids are typically metabolized and used for energy or protein synthesis. D: Increased urine production does not help more water remain in the bloodstream. Excess water is typically excreted to maintain fluid balance.

Correct Answer: C

Rationale: The correct answer is C: kidney. The nephron is the structural unit of the kidney responsible for filtering and processing blood to produce urine. The kidney's primary function is to regulate water and electrolyte balance in the body. Choices A, B, and D are incorrect because the nephron is not found in the lung, liver, or intestine. Each of these organs has its own specialized structures and functions unrelated to the nephron's role in kidney function.

Correct Answer: A

Rationale: The correct answer is A: Duodenal ulcer. The patient's symptoms of pain relieved by food intake and waking up at night with stomach pain are classic signs of a duodenal ulcer. The pain is alleviated by neutralizing gastric acid with food and worsens when the stomach is empty. Gastric ulcers typically worsen with food intake and are associated with weight loss. Esophageal ulcers present with difficulty swallowing and chest pain. Refractory ulcers are those that do not heal despite treatment. Therefore, based on the patient's symptoms, a duodenal ulcer is the most likely diagnosis.