Physiology Exam 3 Bank: Complete 2026/2027
Exam Test Practice Questions and Detailed
Answers for All Sections | Comprehensive
Study Guide and Practice Test
Quiz what is a molecule that is similar in structure to a messenger and binds with that
messenger's receptor to stimulate a similar response from the target cell?
<Ans> agonist
Quiz Which of the following are proteins on a target cell that specifically recognize and bind
only one messenger or a class of messengers?
<Ans> receptors
Quiz The location of receptors on a target cell depends on the solubility of the chemical
messenger. Where would the receptors for lipophilic messengers be located?
<Ans> on the inside of the cell
Quiz Which of the following second messengers activates protein kinase A?
<Ans> cyclic adenosine monophosphate (cAMP
Quiz If a patient were experiencing a less than ideal reaction to a drug, you could try to treat
the patient with another drug that interfered with the first drug. Which of the following types
of drug would be your best option for this?
<Ans> an antagonist drug with greater affinity. This chemical would bind more readily with the
target cell receptors and oppose the action of the initial drug.
Quiz Which of the following proteins is directly activated by a G protein?
,<Ans> adenylate cyclase
Quiz Heroin overdose is usually treated with an opioid __________such as naloxone (Narcan)
or naltrexone, an opioid, which prevents heroin from binding to mu receptors and reverses the
effects of heroin on the body.
<Ans> antagonist
Quiz All beta adrenergic receptors are __________.
<Ans> G protein-linked receptors. Beta receptors are a subclass of adrenergic receptors, which
are G protein-linked receptors.
Quiz What chemical messenger is released by a presynaptic cell?
<Ans> neurotransmitter
Quiz As a general rule, the magnitude of a target cells response to a chemical messenger
depends on which three factors?
<Ans> (1) the concentration of the messenger, (2) the number of receptors and, (3) the affinity
of the receptor for the messenger
Quiz Cholera is the leading cause of death in children in developing countries, characterized by
massive diarrhea. The effects stem from an extracellular toxin that the bacterium Vibrio
cholerae releases into the gut. The toxin acts on a __________ that overstimulates __________
which causes a cascade of events that leads to electrolytes leaving the cell and causing water to
follow them into the lumen of the intestine, resulting in severe diarrhea.
<Ans> G proteins : adenylate cyclase
Quiz The strength of binding between a messenger and its receptor is known as __________.
<Ans> affinity
Quiz In chemical communication between cells, a ________ cell secretes a chemical messenger
that binds to ________ on the ________ cell.
, <Ans> secretory : receptors : target
Quiz What molecule, whose synthesis is catalyzed by phospholipase C, triggers the release of
calcium from the endoplasmic reticulum?
<Ans> inositol triphosphate
Quiz Chronic exposure to a ligand (messenger) ________ the receptor population for that
chemical messenger on the target cell.
<Ans> downregulates
Quiz One of the striking features of second messengers is the ability to elicit a marked response
on a target cell by small changes in the concentration of a chemical messenger. This
phenomenon is known a(n) __________.
<Ans> signal amplification
Quiz Which of the following are second messengers?
<Ans> cAMP, calcium, and inositol triphosphate
Quiz Which of the following statements about G proteins is true?
<Ans> G-proteins can increase or decrease enzyme activity. Gi proteins are inhibitory, and Gs
proteins are stimulatory.
Quiz The ultimate problem with cholera that can lead to death is __________.
<Ans> severe dehydration and electrolyte imbalance
Quiz The loss of chloride ions is occurring as a result of an continuously open __________,
found in certain intestinal epithelial cells.
<Ans> chloride channel protein
Quiz The main purpose of the chloride channel proteins on the apical surface of the intestinal
epithelial cells is to create an osmotic gradient that ultimately causes __________ to move
Exam Test Practice Questions and Detailed
Answers for All Sections | Comprehensive
Study Guide and Practice Test
Quiz what is a molecule that is similar in structure to a messenger and binds with that
messenger's receptor to stimulate a similar response from the target cell?
<Ans> agonist
Quiz Which of the following are proteins on a target cell that specifically recognize and bind
only one messenger or a class of messengers?
<Ans> receptors
Quiz The location of receptors on a target cell depends on the solubility of the chemical
messenger. Where would the receptors for lipophilic messengers be located?
<Ans> on the inside of the cell
Quiz Which of the following second messengers activates protein kinase A?
<Ans> cyclic adenosine monophosphate (cAMP
Quiz If a patient were experiencing a less than ideal reaction to a drug, you could try to treat
the patient with another drug that interfered with the first drug. Which of the following types
of drug would be your best option for this?
<Ans> an antagonist drug with greater affinity. This chemical would bind more readily with the
target cell receptors and oppose the action of the initial drug.
Quiz Which of the following proteins is directly activated by a G protein?
,<Ans> adenylate cyclase
Quiz Heroin overdose is usually treated with an opioid __________such as naloxone (Narcan)
or naltrexone, an opioid, which prevents heroin from binding to mu receptors and reverses the
effects of heroin on the body.
<Ans> antagonist
Quiz All beta adrenergic receptors are __________.
<Ans> G protein-linked receptors. Beta receptors are a subclass of adrenergic receptors, which
are G protein-linked receptors.
Quiz What chemical messenger is released by a presynaptic cell?
<Ans> neurotransmitter
Quiz As a general rule, the magnitude of a target cells response to a chemical messenger
depends on which three factors?
<Ans> (1) the concentration of the messenger, (2) the number of receptors and, (3) the affinity
of the receptor for the messenger
Quiz Cholera is the leading cause of death in children in developing countries, characterized by
massive diarrhea. The effects stem from an extracellular toxin that the bacterium Vibrio
cholerae releases into the gut. The toxin acts on a __________ that overstimulates __________
which causes a cascade of events that leads to electrolytes leaving the cell and causing water to
follow them into the lumen of the intestine, resulting in severe diarrhea.
<Ans> G proteins : adenylate cyclase
Quiz The strength of binding between a messenger and its receptor is known as __________.
<Ans> affinity
Quiz In chemical communication between cells, a ________ cell secretes a chemical messenger
that binds to ________ on the ________ cell.
, <Ans> secretory : receptors : target
Quiz What molecule, whose synthesis is catalyzed by phospholipase C, triggers the release of
calcium from the endoplasmic reticulum?
<Ans> inositol triphosphate
Quiz Chronic exposure to a ligand (messenger) ________ the receptor population for that
chemical messenger on the target cell.
<Ans> downregulates
Quiz One of the striking features of second messengers is the ability to elicit a marked response
on a target cell by small changes in the concentration of a chemical messenger. This
phenomenon is known a(n) __________.
<Ans> signal amplification
Quiz Which of the following are second messengers?
<Ans> cAMP, calcium, and inositol triphosphate
Quiz Which of the following statements about G proteins is true?
<Ans> G-proteins can increase or decrease enzyme activity. Gi proteins are inhibitory, and Gs
proteins are stimulatory.
Quiz The ultimate problem with cholera that can lead to death is __________.
<Ans> severe dehydration and electrolyte imbalance
Quiz The loss of chloride ions is occurring as a result of an continuously open __________,
found in certain intestinal epithelial cells.
<Ans> chloride channel protein
Quiz The main purpose of the chloride channel proteins on the apical surface of the intestinal
epithelial cells is to create an osmotic gradient that ultimately causes __________ to move
