BIOL251 Human Anatomy & Physiology I
w/Lab 2026 | Module 9 Exam
Question 1
Which characteristic distinguishes endocrine glands from exocrine glands?
A. Presence of ducts
B. Lack of ducts
C. Secretion of enzymes
D. Connection to skin
ANSWER: B
Rationale: A) Incorrect, endocrine glands lack ducts. B) Correct, they are ductless and secrete directly
into blood. C) Incorrect, exocrine glands typically secrete enzymes. D) Incorrect, exocrine glands connect
to epithelial surfaces.
Question 2
Hormones are defined as chemical messengers that are:
A. Secreted into ducts
B. Secreted into the blood
C. Produced by neurons only
D. Active only at the site of production
ANSWER: B
Rationale: A) Incorrect, this describes exocrine secretions. B) Correct, hormones are secreted into the
bloodstream to travel to target cells. C) Incorrect, neurotransmitters are produced by neurons. D)
Incorrect, hormones act on distant target cells.
Question 3
A target cell must have what to respond to a specific hormone?
A. A nucleus
,B. A specific receptor
C. A duct
D. A mitochondrion
ANSWER: B
Rationale: A) Incorrect, not all target cells have a nucleus (e.g., RBCs). B) Correct, specificity is
determined by the presence of specific receptors. C) Incorrect, endocrine glands lack ducts. D) Incorrect,
mitochondria are for energy, not hormone specificity.
Question 4
Which class of hormones is derived from cholesterol?
A. Peptides
B. Proteins
C. Steroids
D. Amines
ANSWER: C
Rationale: A) Incorrect, peptides are made of amino acids. B) Incorrect, proteins are made of amino
acids. C) Correct, steroid hormones are synthesized from cholesterol. D) Incorrect, amines are derived
from tyrosine.
Question 5
Which of the following is an amino acid-based hormone?
A. Cortisol
B. Testosterone
C. Epinephrine
D. Aldosterone
ANSWER: C
Rationale: A) Incorrect, cortisol is a steroid. B) Incorrect, testosterone is a steroid. C) Correct,
epinephrine is an amine derived from tyrosine. D) Incorrect, aldosterone is a steroid.
Question 6
How do lipid-soluble hormones primarily travel in the blood?
A. Dissolved freely in plasma
B. Bound to transport proteins
,C. Inside red blood cells
D. Attached to platelets
ANSWER: B
Rationale: A) Incorrect, they are not water-soluble. B) Correct, they bind to carrier proteins to remain
soluble in blood. C) Incorrect, they do not enter RBCs. D) Incorrect, they do not bind to platelets.
Question 7
What is the typical half-life of lipid-soluble hormones compared to water-soluble ones?
A. Shorter
B. Longer
C. Exactly the same
D. Zero
ANSWER: B
Rationale: A) Incorrect, water-soluble have shorter half-lives. B) Correct, binding to proteins protects
them from degradation, giving them a longer half-life. C) Incorrect, they differ significantly. D) Incorrect,
all hormones have a measurable half-life.
Question 8
Water-soluble hormones typically interact with receptors located:
A. Inside the nucleus
B. In the cytoplasm
C. On the cell surface membrane
D. Inside the mitochondria
ANSWER: C
Rationale: A) Incorrect, lipid-soluble hormones bind intracellularly. B) Incorrect, lipid-soluble bind in
cytoplasm. C) Correct, water-soluble hormones cannot cross the membrane and bind surface receptors.
D) Incorrect, receptors are not mitochondrial.
Question 9
Which second messenger is commonly activated by water-soluble hormones like epinephrine?
A. cAMP
B. DNA
C. RNA
, D. ATP
ANSWER: A
Rationale: A) Correct, cyclic AMP is a classic second messenger for catecholamines. B) Incorrect, DNA is
genetic material. C) Incorrect, RNA is for protein synthesis. D) Incorrect, ATP is an energy molecule, not a
second messenger in this context.
Question 10
Up-regulation of a receptor occurs when:
A. Hormone levels are chronically high
B. Hormone levels are chronically low
C. The cell is dead
D. The hormone is destroyed
ANSWER: B
Rationale: A) Incorrect, high levels cause down-regulation. B) Correct, low hormone levels cause the cell
to increase receptor numbers to increase sensitivity. C) Incorrect, dead cells do not regulate. D)
Incorrect, destruction does not cause up-regulation.
Question 11
The hypothalamus controls the anterior pituitary via:
A. Neural impulses
B. The hypophyseal portal system
C. Direct blood arteries
D. The lymphatic system
ANSWER: B
Rationale: A) Incorrect, neural control is for the posterior pituitary. B) Correct, releasing/inhibiting
hormones travel via this portal blood system. C) Incorrect, it is a specialized portal capillary network. D)
Incorrect, lymphatics do not control the pituitary.
Question 12
The posterior pituitary gland is technically part of the:
A. Endocrine system only
B. Digestive system
C. Nervous system
D. Respiratory system
w/Lab 2026 | Module 9 Exam
Question 1
Which characteristic distinguishes endocrine glands from exocrine glands?
A. Presence of ducts
B. Lack of ducts
C. Secretion of enzymes
D. Connection to skin
ANSWER: B
Rationale: A) Incorrect, endocrine glands lack ducts. B) Correct, they are ductless and secrete directly
into blood. C) Incorrect, exocrine glands typically secrete enzymes. D) Incorrect, exocrine glands connect
to epithelial surfaces.
Question 2
Hormones are defined as chemical messengers that are:
A. Secreted into ducts
B. Secreted into the blood
C. Produced by neurons only
D. Active only at the site of production
ANSWER: B
Rationale: A) Incorrect, this describes exocrine secretions. B) Correct, hormones are secreted into the
bloodstream to travel to target cells. C) Incorrect, neurotransmitters are produced by neurons. D)
Incorrect, hormones act on distant target cells.
Question 3
A target cell must have what to respond to a specific hormone?
A. A nucleus
,B. A specific receptor
C. A duct
D. A mitochondrion
ANSWER: B
Rationale: A) Incorrect, not all target cells have a nucleus (e.g., RBCs). B) Correct, specificity is
determined by the presence of specific receptors. C) Incorrect, endocrine glands lack ducts. D) Incorrect,
mitochondria are for energy, not hormone specificity.
Question 4
Which class of hormones is derived from cholesterol?
A. Peptides
B. Proteins
C. Steroids
D. Amines
ANSWER: C
Rationale: A) Incorrect, peptides are made of amino acids. B) Incorrect, proteins are made of amino
acids. C) Correct, steroid hormones are synthesized from cholesterol. D) Incorrect, amines are derived
from tyrosine.
Question 5
Which of the following is an amino acid-based hormone?
A. Cortisol
B. Testosterone
C. Epinephrine
D. Aldosterone
ANSWER: C
Rationale: A) Incorrect, cortisol is a steroid. B) Incorrect, testosterone is a steroid. C) Correct,
epinephrine is an amine derived from tyrosine. D) Incorrect, aldosterone is a steroid.
Question 6
How do lipid-soluble hormones primarily travel in the blood?
A. Dissolved freely in plasma
B. Bound to transport proteins
,C. Inside red blood cells
D. Attached to platelets
ANSWER: B
Rationale: A) Incorrect, they are not water-soluble. B) Correct, they bind to carrier proteins to remain
soluble in blood. C) Incorrect, they do not enter RBCs. D) Incorrect, they do not bind to platelets.
Question 7
What is the typical half-life of lipid-soluble hormones compared to water-soluble ones?
A. Shorter
B. Longer
C. Exactly the same
D. Zero
ANSWER: B
Rationale: A) Incorrect, water-soluble have shorter half-lives. B) Correct, binding to proteins protects
them from degradation, giving them a longer half-life. C) Incorrect, they differ significantly. D) Incorrect,
all hormones have a measurable half-life.
Question 8
Water-soluble hormones typically interact with receptors located:
A. Inside the nucleus
B. In the cytoplasm
C. On the cell surface membrane
D. Inside the mitochondria
ANSWER: C
Rationale: A) Incorrect, lipid-soluble hormones bind intracellularly. B) Incorrect, lipid-soluble bind in
cytoplasm. C) Correct, water-soluble hormones cannot cross the membrane and bind surface receptors.
D) Incorrect, receptors are not mitochondrial.
Question 9
Which second messenger is commonly activated by water-soluble hormones like epinephrine?
A. cAMP
B. DNA
C. RNA
, D. ATP
ANSWER: A
Rationale: A) Correct, cyclic AMP is a classic second messenger for catecholamines. B) Incorrect, DNA is
genetic material. C) Incorrect, RNA is for protein synthesis. D) Incorrect, ATP is an energy molecule, not a
second messenger in this context.
Question 10
Up-regulation of a receptor occurs when:
A. Hormone levels are chronically high
B. Hormone levels are chronically low
C. The cell is dead
D. The hormone is destroyed
ANSWER: B
Rationale: A) Incorrect, high levels cause down-regulation. B) Correct, low hormone levels cause the cell
to increase receptor numbers to increase sensitivity. C) Incorrect, dead cells do not regulate. D)
Incorrect, destruction does not cause up-regulation.
Question 11
The hypothalamus controls the anterior pituitary via:
A. Neural impulses
B. The hypophyseal portal system
C. Direct blood arteries
D. The lymphatic system
ANSWER: B
Rationale: A) Incorrect, neural control is for the posterior pituitary. B) Correct, releasing/inhibiting
hormones travel via this portal blood system. C) Incorrect, it is a specialized portal capillary network. D)
Incorrect, lymphatics do not control the pituitary.
Question 12
The posterior pituitary gland is technically part of the:
A. Endocrine system only
B. Digestive system
C. Nervous system
D. Respiratory system
