What is the hormone produced by adipose tissue which signals satiety?

Correct Answer: B

Rationale: Leptin is the correct answer because it is a hormone produced by adipose tissue that signals satiety to the brain, helping regulate energy balance and food intake. Melatonin is a hormone that regulates sleep-wake cycles, not hunger. Thymosins are involved in immune function. Glucagon is a hormone that increases blood sugar levels, not related to satiety.

Correct Answer: C

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

Correct Answer: A

Rationale: The correct answer is A because blood vessels in the gut are not innervated by the enteric nervous system. The enteric nervous system primarily regulates gut motility, secretion, and blood flow, but it does not innervate blood vessels. The myenteric plexus lies between the longitudinal and circular muscle layers, making choice B correct. Parasympathetic supply to the gut comes from the vagus nerve and sacral nerves, supporting choice C. Sympathetic supply is often inhibitory on cholinergic postganglionic fibers, making choice D accurate. Therefore, A is incorrect as the enteric nervous system does not innervate blood vessels in the gut.

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.