Thyroid hormone synthesis — Flashcards

Flashcard 1: Iodide is taken up into the thyroid follicular cell via _____.

Answer: Na+-iodide symporter

Flashcard 2: Overall, the effects of thyroid hormones are _____ (anabolic, catabolic)

Answer: catabolic

Flashcard 3: What effect does excessive I- intake have on thyroid hormone secretion?_____

Answer: Decreases secretion (Wolff-Chaikoff effect)

Flashcard 4: Exposure to cold temperatures causes increased activation of _____ hormone

Answer: thyroid

Flashcard 5: Which thyroid hormone (T4 or T3) binds to nuclear receptor with greater affinity?_____

Answer: T3

Flashcard 6: What thyroid hormone is more potent?_____

Answer: T3 (10 x more potent than T4)

Flashcard 7: What is the effect of the FGF gene?

Answer: stimulates mitosis of underlying mesoderm, lengthening of limbs

Flashcard 8: What is the embryological origin of the adrenal medulla?

Answer: Neural crest cells

Extra: The adrenal medulla is essentially a modified sympathetic ganglion. While the medulla is derived from the neural crest (ectoderm), the adrenal cortex is derived from the mesoderm.

Flashcard 9: Identify the structure labeled '10' in the provided image of the spinal cord (Endocrine/Autonomic context).

Answer: Intermediate horn (Sympathetics) :: number 10 in the diagram

Flashcard 10: Effect of a lesion to the Reticular Activating System (RAS)?

Answer: Reduced wakefulness and arousability (e.g., coma)