Advanced Pathophysiology Exam 3 2024-2025

1. Thyroid-stimulating hormone (TSH) is released to stimulate thyroid hormone (TH) and is inhibited when plasma levels of TH are adequate. This is an example of: a. Positive feedback b. Neural regulation c. Negative feedback d. Physiologic regulation - ANSWER>>Negative feedback. Feedback systems provide precise monitoring and control of the cellular environment. Negative feedback occurs because the changing chemical, neural, or endocrine response to a stimulus negates the initiating change that triggered the release of the hormone. Thyrotropin-releasing hormone (TRH) from the hypothalamus stimulates TSH secretion from the anterior pituitary. Secretion of TSH stimulates the synthesis and secretion of THs. Increasing levels of T4 and triiodothyronine (T3) then generate negative feedback on the pituitary and hypothalamus to inhibit TRH and TSH synthesis. 1. The releasing hormones that are made in the hypothalamus travel to the anterior pituitary via the: a. Vessels of the zona fasciculata b. Hypophyseal stalk c. Infundibular stem d. Portal hypophyseal blood vessels >>Releasing and inhibitory hormones are Portal hypophyseal blood vessels. - ANSWERsynthesized in the hypothalamus and are secreted into the portal blood vessels through which they travel to the anterior pituitary hormones. 1. Which mineral is needed for thyroid-stimulating hormone (TSH) to stimulate the secretion