4.1.2 Endocrinology (HPT axis)

Question 1

Interrelationships among the hypothalamus, which controls the anterior pituitary, which controls certain target organs (such as adrenal cortex, thyroid, or gonads)

Answer 1

Hypothalamic-Pituitary-Target Organ Axis

Question 2

Inhibitory

a. Positive feedback
b. Negative feedback

Answer 2

b

Question 3

Stimulatory

a. Positive feedback
b. Negative feedback

Answer 3

a

Question 4

In positive feedback:

The hypothalamus secretes Thyrotropin-releasing hormone which stimulates the ____________ to secrete TSH.

Answer 4

anterior pituitary

Question 5

In positive feedback:

The TSH stimulates the thyroid to secrete?

Answer 5

T3 and T4

Question 6

Negative feedback:

Excessive T3 / T4 alerts the Hypothalamus and anterior pituitary gland to inhibit the secretion of T3 and T4

a. Long feedback loop
b. Short feedback loop
c. Ultrashort feed back loop

Answer 6

a

Distant site

Question 7

Negative feedback:

TSH from anterior pituitary gland feedbacks to the hypothalamus due to excessive TSH which inhibits further secretion of TRH

a. Long feedback loop
b. Short feedback loop
c. Ultrashort feed back loop

Answer 7

b

Question 8

Negative feedback:

A hormone produced by the anterior pituitary feedback negatively at the SAME anterior pituitary

a. Long feedback loop
b. Short feedback loop
c. Ultrashort feed back loop

Answer 8

c

Question 9

Defect in target organ

a. Primary disorders
b. Secondary disorders
c. Tertiary disorders

Answer 9

a

Question 10

Defect in hypothalamus

a. Primary disorders
b. Secondary disorders
c. Tertiary disorders

Answer 10

c

Question 11

Defect in the anterior pituitary gland

a. Primary disorders
b. Secondary disorders
c. Tertiary disorders

Answer 11

b