BIOD 331 PATHOPHYSIOLOGY EXAM 4
SCRIPT COMPLETE ANSWERS GRADED
A+
◉ Secretion of thyroid hormones is stimulated by __________
Answer: Thyrotropin (TSH)
◉ Thyroid hormones include __________ and require ________for
synthesis
Answer: T3, T4
Iodine
◉ Secretion of T3 & T4:
Answer: *The majority of T3 and T4 are reversibly bound to
plasma protein for transport
*T4 serves as a pro-hormone for T3
*T3 has a greater affinity for target cell receptor sites than T4
◉ Secretion of thyroid hormones is inhibited by:
Answer: A negative feedback loop
,◉ High circulating levels of T3 and T4 ___________ the secretion of
__________ from the ______________
Answer: *inhibit
*TSH (thyrotropin)
*anterior pituitary
◉ High circulating levels of T3 and T4 ____________secretion of
____________ from the _________ (thus indirectly inhibiting secretion
of TSH)
Answer: *inhibit
*TRH (thyrotropin releasing hormone)
*hypothalamus
◉ Effects of thyroid hormone:
Answer: *Increases basal metabolic rate, heat production, and
stimulates O2 consumption
*Promotes bone and brain growth
, *Increases rate of carb absorption, protein synthesis, and lipid
catabolism
*Stimulates the nervous system
*Stimulates cardiac rate and contractility
◉ Goiter: definition
Answer: Diffuse enlargement of the thyroid gland due to
prolonged stimulation of thyroid stimulating hormone (TSH) or
TSH-like agent
May be associated with hypo or hyperthyroidism
◉ Goiter - associated with hypothyroidism. The most common
cause in developing countries?
Answer: Dietary iodine deficiency
◉ Goiter - associated with hypothyroidism. Other causes?
Answer: *Hashimoto's thyroiditis
*Ingestion of goitrogenic medications (block synthesis of thyroid
hormones)
*Congenital disorders
SCRIPT COMPLETE ANSWERS GRADED
A+
◉ Secretion of thyroid hormones is stimulated by __________
Answer: Thyrotropin (TSH)
◉ Thyroid hormones include __________ and require ________for
synthesis
Answer: T3, T4
Iodine
◉ Secretion of T3 & T4:
Answer: *The majority of T3 and T4 are reversibly bound to
plasma protein for transport
*T4 serves as a pro-hormone for T3
*T3 has a greater affinity for target cell receptor sites than T4
◉ Secretion of thyroid hormones is inhibited by:
Answer: A negative feedback loop
,◉ High circulating levels of T3 and T4 ___________ the secretion of
__________ from the ______________
Answer: *inhibit
*TSH (thyrotropin)
*anterior pituitary
◉ High circulating levels of T3 and T4 ____________secretion of
____________ from the _________ (thus indirectly inhibiting secretion
of TSH)
Answer: *inhibit
*TRH (thyrotropin releasing hormone)
*hypothalamus
◉ Effects of thyroid hormone:
Answer: *Increases basal metabolic rate, heat production, and
stimulates O2 consumption
*Promotes bone and brain growth
, *Increases rate of carb absorption, protein synthesis, and lipid
catabolism
*Stimulates the nervous system
*Stimulates cardiac rate and contractility
◉ Goiter: definition
Answer: Diffuse enlargement of the thyroid gland due to
prolonged stimulation of thyroid stimulating hormone (TSH) or
TSH-like agent
May be associated with hypo or hyperthyroidism
◉ Goiter - associated with hypothyroidism. The most common
cause in developing countries?
Answer: Dietary iodine deficiency
◉ Goiter - associated with hypothyroidism. Other causes?
Answer: *Hashimoto's thyroiditis
*Ingestion of goitrogenic medications (block synthesis of thyroid
hormones)
*Congenital disorders
