,BIOL331/BIOL 331 Module 9
Pathophysiology | Portage |Q&A| 26/27
Actual (PDF)
1. A physiologist is studying the mechanism by which a hormone exerts its effect on the very cell that
synthesized and released it. Which type of signaling is being described?
A) Endocrine signaling
B) Paracrine signaling
C) Autocrine signaling
D) Neuroendocrine signaling
Correct Answer: Autocrine signaling
Rationale: Autocrine signaling occurs when a hormone or chemical messenger acts on the same cell
that produced it, allowing self-regulation. Endocrine signaling involves hormones traveling through
the bloodstream to distant target cells, paracrine signaling acts on nearby cells, and neuroendocrine
signaling involves neurons releasing hormones into the blood, making them incorrect.
2. A researcher is examining a signaling mechanism where a hormone diffuses through extracellular
fluid to affect neighboring cells without entering the bloodstream. Which type of signaling is this?
A) Endocrine signaling
B) Paracrine signaling
C) Autocrine signaling
,D) Synaptic signaling
Correct Answer: Paracrine signaling
Rationale: Paracrine signaling involves the release of a chemical mediator that diffuses through the
extracellular fluid to act on neighboring target cells without entering the bloodstream. Endocrine
signaling uses the bloodstream for distant targets, autocrine signaling acts on the producing cell, and
synaptic signaling involves neurotransmitter release at synapses, making them incorrect.
3. A student is examining the classic definition of endocrine signaling. Which statement accurately
describes this process?
A) Hormones act locally on cells near where they are released
B) Hormones are released into circulation to act on a target organ
C) Hormones act on the same cell that produced them
D) Hormones cross a synaptic cleft to reach a postsynaptic neuron
Correct Answer: Hormones are released into circulation to act on a target organ
Rationale: Endocrine signaling involves glands releasing hormones directly into the bloodstream,
allowing them to travel to distant target organs. Paracrine signaling acts on nearby cells, autocrine
signaling acts on the producing cell, and synaptic signaling crosses a synaptic cleft, making them
incorrect.
4. A researcher is studying the role of transport proteins in hormone circulation. Which statement
about hormone transport is accurate?
A) All hormones travel through the bloodstream attached to transport carriers
, B) Only peptide hormones require transport carriers
C) Steroid and thyroid hormones are bound to plasma transport proteins
D) Hormones cannot travel freely dissolved in plasma
Correct Answer: Steroid and thyroid hormones are bound to plasma transport proteins
Rationale: Steroid and thyroid hormones are lipophilic and require plasma transport proteins to travel
through the bloodstream, while many peptide hormones travel freely dissolved in plasma. Not all
hormones require carriers, peptide hormones generally do not, and hormones can travel freely,
making them incorrect.
5. A physiologist is examining the requirement for a hormone to produce a cellular response. What
must a target cell possess to respond to a hormone?
A) Specific receptors for the hormone
B) Transport proteins for the hormone
C) Enzymes to degrade the hormone
D) Channels for the hormone to enter
Correct Answer: Specific receptors for the hormone
Rationale: Target cells must have specific receptors to recognize a hormone and translate the signal
into a cellular response. Transport proteins are for hormone carriage in blood, enzymes degrade
hormones, and channels are for ion movement, making them incorrect.
Pathophysiology | Portage |Q&A| 26/27
Actual (PDF)
1. A physiologist is studying the mechanism by which a hormone exerts its effect on the very cell that
synthesized and released it. Which type of signaling is being described?
A) Endocrine signaling
B) Paracrine signaling
C) Autocrine signaling
D) Neuroendocrine signaling
Correct Answer: Autocrine signaling
Rationale: Autocrine signaling occurs when a hormone or chemical messenger acts on the same cell
that produced it, allowing self-regulation. Endocrine signaling involves hormones traveling through
the bloodstream to distant target cells, paracrine signaling acts on nearby cells, and neuroendocrine
signaling involves neurons releasing hormones into the blood, making them incorrect.
2. A researcher is examining a signaling mechanism where a hormone diffuses through extracellular
fluid to affect neighboring cells without entering the bloodstream. Which type of signaling is this?
A) Endocrine signaling
B) Paracrine signaling
C) Autocrine signaling
,D) Synaptic signaling
Correct Answer: Paracrine signaling
Rationale: Paracrine signaling involves the release of a chemical mediator that diffuses through the
extracellular fluid to act on neighboring target cells without entering the bloodstream. Endocrine
signaling uses the bloodstream for distant targets, autocrine signaling acts on the producing cell, and
synaptic signaling involves neurotransmitter release at synapses, making them incorrect.
3. A student is examining the classic definition of endocrine signaling. Which statement accurately
describes this process?
A) Hormones act locally on cells near where they are released
B) Hormones are released into circulation to act on a target organ
C) Hormones act on the same cell that produced them
D) Hormones cross a synaptic cleft to reach a postsynaptic neuron
Correct Answer: Hormones are released into circulation to act on a target organ
Rationale: Endocrine signaling involves glands releasing hormones directly into the bloodstream,
allowing them to travel to distant target organs. Paracrine signaling acts on nearby cells, autocrine
signaling acts on the producing cell, and synaptic signaling crosses a synaptic cleft, making them
incorrect.
4. A researcher is studying the role of transport proteins in hormone circulation. Which statement
about hormone transport is accurate?
A) All hormones travel through the bloodstream attached to transport carriers
, B) Only peptide hormones require transport carriers
C) Steroid and thyroid hormones are bound to plasma transport proteins
D) Hormones cannot travel freely dissolved in plasma
Correct Answer: Steroid and thyroid hormones are bound to plasma transport proteins
Rationale: Steroid and thyroid hormones are lipophilic and require plasma transport proteins to travel
through the bloodstream, while many peptide hormones travel freely dissolved in plasma. Not all
hormones require carriers, peptide hormones generally do not, and hormones can travel freely,
making them incorrect.
5. A physiologist is examining the requirement for a hormone to produce a cellular response. What
must a target cell possess to respond to a hormone?
A) Specific receptors for the hormone
B) Transport proteins for the hormone
C) Enzymes to degrade the hormone
D) Channels for the hormone to enter
Correct Answer: Specific receptors for the hormone
Rationale: Target cells must have specific receptors to recognize a hormone and translate the signal
into a cellular response. Transport proteins are for hormone carriage in blood, enzymes degrade
hormones, and channels are for ion movement, making them incorrect.
