NUR 631 Endocrinology Exam 2026/2027 –
Comprehensive Complete Questions & Verified
Answers with Rationales
Coverage: Endocrine physiology, diabetes mellitus, thyroid disorders, adrenal
disorders, pituitary disease, calcium/parathyroid disorders, reproductive
endocrinology, endocrine tumors, metabolic disease, diagnostics, and
pharmacologic principles.
Section I — Endocrine Physiology and Regulatory Systems
1. Which characteristic best describes a peptide hormone?
A. It readily crosses the plasma membrane
B. It is generally stored in secretory vesicles
C. It binds only intracellular receptors
D. It is synthesized exclusively from cholesterol
Answer: B
Rationale: Peptide hormones are synthesized as precursor proteins and
commonly stored in secretory vesicles until released by exocytosis. They generally
bind cell-surface receptors because they do not readily cross lipid membranes.
2. Which hormone primarily acts through an intracellular receptor?
A. Insulin
B. Glucagon
C. Cortisol
D. Epinephrine
Answer: C
Rationale: Cortisol is lipid soluble and crosses cell membranes to bind intracellular
glucocorticoid receptors, altering gene transcription.
,3. A patient has increased cortisol that suppresses both CRH and ACTH. This
illustrates:
A. Positive feedback
B. Feed-forward activation
C. Negative feedback
D. Receptor downregulation
Answer: C
Rationale: Cortisol inhibits hypothalamic CRH and pituitary ACTH secretion,
providing classic negative feedback within the HPA axis.
4. Which second messenger is strongly associated with ACTH receptor signaling?
A. cAMP
B. cGMP only
C. Intracellular DNA
D. Tyrosine phosphorylation exclusively
Answer: A
Rationale: The melanocortin-2 receptor for ACTH is a G-protein-coupled receptor
that primarily activates adenylate cyclase and cAMP.
5. Insulin signaling is most closely associated with which receptor type?
A. Nuclear steroid receptor
B. Receptor tyrosine kinase
C. Ligand-gated chloride channel
D. Intracellular calcium receptor
Answer: B
Rationale: The insulin receptor is a receptor tyrosine kinase. Activation initiates
phosphorylation cascades involving IRS proteins and downstream pathways
affecting glucose, lipid, and protein metabolism.
6. Which endocrine gland is often described as the major regulatory gland
because its hormones control multiple peripheral endocrine glands?
,A. Thyroid
B. Adrenal cortex
C. Pituitary
D. Pancreas
Answer: C
Rationale: The anterior pituitary releases trophic hormones such as TSH, ACTH,
LH, and FSH that regulate several peripheral endocrine organs.
7. Which hypothalamic hormone stimulates TSH release?
A. CRH
B. TRH
C. GnRH
D. GHRH
Answer: B
Rationale: Thyrotropin-releasing hormone stimulates pituitary TSH secretion and
can also increase prolactin secretion.
8. Which anterior pituitary hormone primarily stimulates adrenal cortisol
production?
A. TSH
B. ACTH
C. GH
D. FSH
Answer: B
Rationale: ACTH stimulates the adrenal cortex, particularly the zona fasciculata,
promoting glucocorticoid synthesis.
9. Which hypothalamic hormone regulates growth hormone secretion?
A. GHRH
B. TRH
C. CRH
D. Somatostatin only
, Answer: A
Rationale: GHRH stimulates GH secretion, whereas somatostatin inhibits it.
10. Which hormone is produced by pancreatic beta cells?
A. Glucagon
B. Insulin
C. Somatostatin
D. Pancreatic polypeptide
Answer: B
Rationale: Beta cells synthesize and secrete insulin in response to elevated
glucose and other nutrient signals.
11. Pancreatic alpha cells primarily secrete:
A. Insulin
B. Glucagon
C. Amylin
D. Somatostatin
Answer: B
Rationale: Glucagon increases hepatic glucose production, particularly during
fasting or hypoglycemia.
12. Which pancreatic cell secretes somatostatin?
A. Alpha cell
B. Beta cell
C. Delta cell
D. PP cell
Answer: C
Rationale: Delta cells produce somatostatin, which suppresses several
gastrointestinal and pancreatic secretory functions.
13. What is the primary metabolic effect of insulin?
Comprehensive Complete Questions & Verified
Answers with Rationales
Coverage: Endocrine physiology, diabetes mellitus, thyroid disorders, adrenal
disorders, pituitary disease, calcium/parathyroid disorders, reproductive
endocrinology, endocrine tumors, metabolic disease, diagnostics, and
pharmacologic principles.
Section I — Endocrine Physiology and Regulatory Systems
1. Which characteristic best describes a peptide hormone?
A. It readily crosses the plasma membrane
B. It is generally stored in secretory vesicles
C. It binds only intracellular receptors
D. It is synthesized exclusively from cholesterol
Answer: B
Rationale: Peptide hormones are synthesized as precursor proteins and
commonly stored in secretory vesicles until released by exocytosis. They generally
bind cell-surface receptors because they do not readily cross lipid membranes.
2. Which hormone primarily acts through an intracellular receptor?
A. Insulin
B. Glucagon
C. Cortisol
D. Epinephrine
Answer: C
Rationale: Cortisol is lipid soluble and crosses cell membranes to bind intracellular
glucocorticoid receptors, altering gene transcription.
,3. A patient has increased cortisol that suppresses both CRH and ACTH. This
illustrates:
A. Positive feedback
B. Feed-forward activation
C. Negative feedback
D. Receptor downregulation
Answer: C
Rationale: Cortisol inhibits hypothalamic CRH and pituitary ACTH secretion,
providing classic negative feedback within the HPA axis.
4. Which second messenger is strongly associated with ACTH receptor signaling?
A. cAMP
B. cGMP only
C. Intracellular DNA
D. Tyrosine phosphorylation exclusively
Answer: A
Rationale: The melanocortin-2 receptor for ACTH is a G-protein-coupled receptor
that primarily activates adenylate cyclase and cAMP.
5. Insulin signaling is most closely associated with which receptor type?
A. Nuclear steroid receptor
B. Receptor tyrosine kinase
C. Ligand-gated chloride channel
D. Intracellular calcium receptor
Answer: B
Rationale: The insulin receptor is a receptor tyrosine kinase. Activation initiates
phosphorylation cascades involving IRS proteins and downstream pathways
affecting glucose, lipid, and protein metabolism.
6. Which endocrine gland is often described as the major regulatory gland
because its hormones control multiple peripheral endocrine glands?
,A. Thyroid
B. Adrenal cortex
C. Pituitary
D. Pancreas
Answer: C
Rationale: The anterior pituitary releases trophic hormones such as TSH, ACTH,
LH, and FSH that regulate several peripheral endocrine organs.
7. Which hypothalamic hormone stimulates TSH release?
A. CRH
B. TRH
C. GnRH
D. GHRH
Answer: B
Rationale: Thyrotropin-releasing hormone stimulates pituitary TSH secretion and
can also increase prolactin secretion.
8. Which anterior pituitary hormone primarily stimulates adrenal cortisol
production?
A. TSH
B. ACTH
C. GH
D. FSH
Answer: B
Rationale: ACTH stimulates the adrenal cortex, particularly the zona fasciculata,
promoting glucocorticoid synthesis.
9. Which hypothalamic hormone regulates growth hormone secretion?
A. GHRH
B. TRH
C. CRH
D. Somatostatin only
, Answer: A
Rationale: GHRH stimulates GH secretion, whereas somatostatin inhibits it.
10. Which hormone is produced by pancreatic beta cells?
A. Glucagon
B. Insulin
C. Somatostatin
D. Pancreatic polypeptide
Answer: B
Rationale: Beta cells synthesize and secrete insulin in response to elevated
glucose and other nutrient signals.
11. Pancreatic alpha cells primarily secrete:
A. Insulin
B. Glucagon
C. Amylin
D. Somatostatin
Answer: B
Rationale: Glucagon increases hepatic glucose production, particularly during
fasting or hypoglycemia.
12. Which pancreatic cell secretes somatostatin?
A. Alpha cell
B. Beta cell
C. Delta cell
D. PP cell
Answer: C
Rationale: Delta cells produce somatostatin, which suppresses several
gastrointestinal and pancreatic secretory functions.
13. What is the primary metabolic effect of insulin?
