Ch. 17 - Endocrine Physiology

Question 1

What type of hormones are derived from cholesterol?

Answer 1

Steroid hormones

Question 2

What is the route of synthesis for epinephrine?

Answer 2

• Phenylalanine
• Tyrosine
• Dopa
• Dopamine
• Norepinephrine
• Epinephrine

Question 3

Where do steroid, amine and peptide hormones bind?

Answer 3

• Steroids - intracellular receptors
• Amines & Peptides - plasma membrane receptors

Question 4

What are the 3 major classes of second messengers?

Answer 4

1. Cyclic nucleotides (cAMP, cGMP)
2. IP3 and DAG
3. Ca2+ ions

Question 5

What are the 2 causes of diabetes insipidus?

Answer 5

• Central Diabetes (low ADH)
  
  • Destruction of supraoptic nuclei
  • Low activity of posterior pituitary
• Nephrogenic Diabetes (ADH normal or high)
  
  • Renal tubule does not respond to ADH
  • Congenital/familial
  • Drug induced (lithium)

Question 6

What causes an increase of release of Growth Hormone?

Answer 6

• GNRH
• Low plasma glucose concentration
• High plasma level of amino acids (esp arginine)

Question 7

Prolactin is under predominant _________ control.

Answer 7

Inhibitory

Question 8

When is the formation of the primary and secondy oocytes take place?

Answer 8

• Primary - before birth
• Secondary - at ovulation

Question 9

What cells in the pancreas release insulin and which release glucagon?

Answer 9

• Insulin - beta cells of islets of Langerhans
• Glucagon - alpha cells in islets of Langerhans

Question 10

What is the most common endocrine disorder involving the pancreas?

Answer 10

Diabetes Mellitus

Question 11

What is the most important in calcium metabolism?

Answer 11

PTH - Parathyroid Hormone

Question 12

What is the mechanism for aldosterone release?

Answer 12

• Low sodium Na+
• Juxtaglomerular cells secrete renin
• Renin cleaves angiotensinogen into
• AT-1 (converted by ACE)
• AT-II stimulates adrenal cortex to release
• Aldosterone (zona glomerulosa)