Which of the following hormones helps conserve water during dehydration?

Correct Answer: C

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.

Correct Answer: B

Rationale: The correct answer is B: B12. B12 is a water-soluble vitamin because it dissolves in water and can be easily excreted through urine if taken in excess. It plays a crucial role in red blood cell formation and neurological function. Vitamins D, A, and K are fat-soluble vitamins, meaning they require fat for absorption and are stored in the body's fat tissues, making it harder to excrete excess amounts. This is why B12 is the only water-soluble vitamin among the choices.

Correct Answer: C

Rationale: The correct answer is C: peristaltic rushes. Peristaltic rushes are abnormal and excessive contractions that can result in diarrhea or bowel urgency. In normal health, peristalsis (A) is the coordinated contraction and relaxation of intestinal smooth muscles that moves contents along the digestive tract. Weak antiperistalsis (B) refers to reverse contractions that are weaker than normal peristalsis. Tonic contractions (D) are sustained contractions that help maintain muscle tone and control flow. Therefore, peristaltic rushes are the only option that does not occur in normal health due to their abnormal and disruptive nature.

Correct Answer: D

Rationale: Basal metabolic rate (BMR) is the energy expended by the body at rest to maintain basic physiological functions. Choice D is correct because it states that BMR is about 40Kcal/m2/h in an average man, which is a commonly accepted value. This is based on the energy needed for essential bodily functions such as breathing, circulation, and cell production. Choices A, B, and C are incorrect because: A) BMR is generally higher in men due to their higher muscle mass; B) BMR is measured after an overnight fast, not within 12 hours after the last meal; C) Fever typically increases BMR by around 7% per 1°C rise, not 18%.

Correct Answer: C

Rationale: Correct Answer: C Rationale: 1. Endocrine glands are ductless: Endocrine glands release hormones directly into the bloodstream instead of using ducts. 2. Exocrine glands release secretions at the body's surface or into ducts: Exocrine glands release their secretions through ducts to the body's surface or specific locations. 3. Therefore, the key difference is the presence of ducts: Endocrine glands lack ducts, while exocrine glands have ducts for secretion. This distinction makes choice C the correct answer. Summary: A: Incorrect. Endocrine glands and exocrine glands can both be formed by epithelial tissue. B: Incorrect. Exocrine glands release enzymes and other substances, not waste products. D: Incorrect. There is no interconnection requirement for endocrine glands, and exocrine glands can also be interconnected.