Pineal and Thyroid — Prelims Questions

Which of the following hormones is primarily responsible for regulating the sleep-wake cycle in humans?

A patient presents with symptoms including weight loss, increased heart rate, heat intolerance, and nervousness. Blood tests show low TSH levels and high T3/T4 levels. Which of the following conditions is most likely?

Which of the following statements about calcitonin is INCORRECT?

Which of the following is the rate-limiting enzyme in the synthesis of melatonin?

Which of the following is NOT a function of thyroid hormones (T3 and T4)?

A 10-year-old child exhibits stunted growth, mental retardation, and a puffy face. These symptoms are indicative of a deficiency in which of the following?