and answers + explanation 2026 prep solution Queen's University
MODULE 1
SECTION 1.1 — Principles of Endocrinology
1. Which of the following is not a general function of the endocrine system?
A. Homeostasis
B. Adaptive stress response
C. Voluntary skeletal muscle control
D. Red blood cell production
Answer: C
Explanation: Voluntary muscle control is a nervous-system function, not endocrine.
2. A hormone is best defined as…
A. A chemical secreted into ducts to target nearby tissues
B. A chemical secreted into the bloodstream to act on distant tissues
C. A neurotransmitter released across synapses
D. A protein used only for digestion
Answer: B
Explanation: Hormones travel via blood to act on distant target cells.
3. Hydrophilic hormones are generally:
A. Bound to plasma proteins
B. Lipid soluble
C. Free in plasma
D. Able to diffuse across membranes
Answer: C
Explanation: Hydrophilic hormones (peptides, catecholamines) circulate unbound.
,4. Peptide hormones are synthesized initially as:
A. Steroids
B. Cholesterol fragments
C. Preprohormones
D. Fatty acid derivatives
Answer: C
Explanation: Peptide hormones are synthesized as preprohormones, then processed.
5. Lipophilic hormones are typically stored:
,A. In secretory vesicles
B. Bound to cholesterol
C. Not stored; released as synthesized
D. In the nucleus
Answer: C
Explanation: Lipophilic hormones cannot be stored in vesicles and diffuse out immediately.
6. Which of the following is lipophilic?
A. Peptide hormones
B. Catecholamines
C. Thyroid hormone
D. Insulin
Answer: C
Explanation: Thyroid hormones are amine-derived but behave like lipophilic hormones.
7. Steroid hormone synthesis always begins with:
A. Glucose
B. Acetylcholine
C. Cholesterol
D. ATP
Answer: C
Explanation: All steroid hormones derive from cholesterol.
8. Hydrophilic hormones exert their effects primarily through:
A. Secondary messenger systems
B. Direct DNA binding
C. Nuclear receptor complexes
D. Changes in gene transcription only
Answer: A
Explanation: They cannot cross membranes → use surface receptors → second messengers.
9. The cAMP pathway includes activation of:
A. Phospholipase C
B. PKA
C. CaM-Kinase
D. IP3 production
Answer: B
Explanation: cAMP activates protein kinase A (PKA).
10. The IP3/Ca²⁺ pathway results in activation of:
, A. PKA
B. Adenylyl cyclase
C. Calmodulin
D. Cholesterol desmolase
Answer: C
Explanation: IP3 increases Ca²⁺ → binds calmodulin → activates CaM-kinase.
11. Which hormone uses the IP3/Ca²⁺ pathway?
A. Glucagon
B. ACTH
C. TRH
D. Calcitonin
Answer: C
Explanation: TRH is one of the hormones using the IP3/Ca²⁺ system.
12. Lipophilic hormones act by:
A. Activating membrane-bound G proteins
B. Directly opening ion channels
C. Altering gene transcription
D. Stimulating exocytosis of vesicles
Answer: C
Explanation: Lipophilic hormones enter the cell → bind intracellular receptors → alter
transcription.
13. A hormone must be to bind its receptor.
A. Bound to carrier proteins
B. Free/unbound
C. Stored in vesicles
D. Phosphorylated
Answer: B
Explanation: Only free hormone can bind receptors and exert physiological effects.
14. Dynamic equilibrium of lipophilic hormones refers to:
A. Constant degradation in blood
B. Rapid replacement with synthetic hormones
C. Continuous binding/unbinding from carriers
D. Their storage in vesicles
Answer: C
Explanation: Lipophilic hormones move between bound and unbound states.