BIOD 151
Module 6 – Endocrine
System
Final Assessment Review
(With Solutions)
2025
1
,1. A 50-year-old man presents with central obesity, purple striae, and
hypertension. Laboratory studies show elevated plasma cortisol, elevated
ACTH, and no suppression on low-dose dexamethasone test. Which
diagnosis is most likely?
a. Adrenal adenoma
b. Ectopic ACTH–secreting carcinoma
c. Primary adrenal hyperplasia
d. Exogenous glucocorticoid use
ANS: b. Ectopic ACTH–secreting carcinoma
Rationale: Elevated ACTH with no negative feedback and absence of
suppression suggests paraneoplastic ACTH production rather than
pituitary or exogenous source.
2. A 28-year-old woman with type 1 diabetes reports tremor,
palpitations, and diaphoresis 30 minutes after her morning insulin
injection. Which physiologic mechanism explains her hypoglycemia
symptoms?
a. Increased cortisol secretion
b. Sympathetic activation via epinephrine
c. Enhanced glucagon release from α-cells
d. Decreased growth hormone release
ANS: b. Sympathetic activation via epinephrine
Rationale: Sudden insulin–mediated glucose decline triggers adrenal
medullary release of epinephrine, causing adrenergic symptoms.
3. A teenager with untreated Graves’ disease has heat intolerance,
2
, weight loss, and exophthalmos. Which antibody mediates the
pathogenesis?
a. Anti–TSH receptor stimulating antibodies
b. Anti–thyroid peroxidase antibodies
c. Anti–thyroglobulin antibodies
d. Anti–TSH receptor blocking antibodies
ANS: a. Anti–TSH receptor stimulating antibodies
Rationale: Thyroid-stimulating immunoglobulins bind TSH receptors,
driving excessive thyroid hormone synthesis and hyperthyroidism.
4. A 45-year-old patient with chronic kidney disease develops secondary
hyperparathyroidism. Which change in mineral metabolism precipitates
this condition?
a. Increased calcitriol synthesis
b. Elevated serum calcium
c. Reduced phosphate excretion
d. Decreased PTH receptor expression
ANS: c. Reduced phosphate excretion
Rationale: Phosphate retention lowers free calcium and inhibits
calcitriol production, stimulating compensatory PTH secretion.
5. A patient with a prolactin-secreting pituitary adenoma reports
galactorrhea and amenorrhea. Which hypothalamic factor is likely
suppressed?
a. Dopamine
b. Thyrotropin-releasing hormone
c. Growth hormone–releasing hormone
d. Corticotropin-releasing hormone
3
Module 6 – Endocrine
System
Final Assessment Review
(With Solutions)
2025
1
,1. A 50-year-old man presents with central obesity, purple striae, and
hypertension. Laboratory studies show elevated plasma cortisol, elevated
ACTH, and no suppression on low-dose dexamethasone test. Which
diagnosis is most likely?
a. Adrenal adenoma
b. Ectopic ACTH–secreting carcinoma
c. Primary adrenal hyperplasia
d. Exogenous glucocorticoid use
ANS: b. Ectopic ACTH–secreting carcinoma
Rationale: Elevated ACTH with no negative feedback and absence of
suppression suggests paraneoplastic ACTH production rather than
pituitary or exogenous source.
2. A 28-year-old woman with type 1 diabetes reports tremor,
palpitations, and diaphoresis 30 minutes after her morning insulin
injection. Which physiologic mechanism explains her hypoglycemia
symptoms?
a. Increased cortisol secretion
b. Sympathetic activation via epinephrine
c. Enhanced glucagon release from α-cells
d. Decreased growth hormone release
ANS: b. Sympathetic activation via epinephrine
Rationale: Sudden insulin–mediated glucose decline triggers adrenal
medullary release of epinephrine, causing adrenergic symptoms.
3. A teenager with untreated Graves’ disease has heat intolerance,
2
, weight loss, and exophthalmos. Which antibody mediates the
pathogenesis?
a. Anti–TSH receptor stimulating antibodies
b. Anti–thyroid peroxidase antibodies
c. Anti–thyroglobulin antibodies
d. Anti–TSH receptor blocking antibodies
ANS: a. Anti–TSH receptor stimulating antibodies
Rationale: Thyroid-stimulating immunoglobulins bind TSH receptors,
driving excessive thyroid hormone synthesis and hyperthyroidism.
4. A 45-year-old patient with chronic kidney disease develops secondary
hyperparathyroidism. Which change in mineral metabolism precipitates
this condition?
a. Increased calcitriol synthesis
b. Elevated serum calcium
c. Reduced phosphate excretion
d. Decreased PTH receptor expression
ANS: c. Reduced phosphate excretion
Rationale: Phosphate retention lowers free calcium and inhibits
calcitriol production, stimulating compensatory PTH secretion.
5. A patient with a prolactin-secreting pituitary adenoma reports
galactorrhea and amenorrhea. Which hypothalamic factor is likely
suppressed?
a. Dopamine
b. Thyrotropin-releasing hormone
c. Growth hormone–releasing hormone
d. Corticotropin-releasing hormone
3
