Endocrine Practice Questions (Pak)

Question 1

This enzyme has a 2-3 minute half-life. It is stored in the cell’s secretory granules. The rate limiting enzyme is tyrosine hydroxylase. What is the chemical category?

Answer 1

Catecholamine

note: she said she would simply change the criteria

Question 2

A pre-prohormone is characterized by the presence of which one of the following?

A. Copeptide
B. Signal peptide
C. Aromatic ring
E. disulfide bond

Answer 2

B. Signal peptide

Question 3

Some patients take melatonin supplements to alleviate insomnia. Which of the following mechanisms explain low plasma melatonin?

A. Increased dietary intake of tryptophan
B. Genetic defect in N-acetyltransferase
C. long periods of darkness
D. Increased plasma levels of albumin
E. Overproduction of 5-HT

Answer 3

B

Question 4

Assuming a negative feedback system, which one is anticipated with a hypo functioning pituitary (secondary) endocrine effect?

Answer 4

Low levels of peripheral hormone X

High levels of hypothalamic hormone Y

Question 5

Kallman syndrome is a relatively rare disorder that manifests as infertility and anosmia. What explains this link?

Answer 5

GnRH neurons migrate from the olfactory placed to the brain in development, through the cribriform plate, where they end up in the pre optic area (POA) of the hypothalamus!

Question 6

Which of the following is most likely to cause diabetes insipidus?

A. Atrophy of posterior pituitary
B. Lactotroph tumor
C. Destruction of alpha-cells
D. Downregulation of IGF1 receptors
E. Blockage of hypophyseal portal system

Answer 6

A.

Question 7

Type 1 diabetes patients lose weight and experience severe muscle wasting despite eating well. Why?

A. Lack of insulin inhibits ketone body formation
B. Cortisol inhibits gluconeogenesis resulting in lack of normal growth
C. GLUT 4 is sequestered inside the muscle and fat cells
D. GLUT 2 is oversaturated and can’t transport glucose into hepatocytes
E. Excessive IGF1 production exerts negative feedback on GH

Answer 7

C

Question 8

Insulin secretion pattern in pancreatic cells. Substance X directly inhibits insulin secretion. This X is probably…

A. Alpha-2 adrenergic agonist
B. Glucokinase
C. Cholecystokinin
D. GLP-1
E. Increased intracellular Ca2+

Answer 8

A.

Question 9

In a patient with severe hypoglycemia, the differential diagnosis between a self-administered insulin overdose and a tumor that produces excess insulin can be made by determining plasma levels of...
A. Insulin
B. Somatostatin
C. C-peptide
D. Incretins (GLP1/2)
E. Glucagon

Answer 9

C.

Question 10

Which one of the following best describes the action of sulfonyl urea drugs on the pancreatic beta cell?

A. Activates G-alpha-s receptors
B. closes Na+ channels
C. Inhibits insulin release
D. Closes K+ channels
E Increases peripheral insulin sensitivity.

Answer 10

D. Closes K+ channels