ALL EXAM MASTER PA-CAT
QUESTIONS WITH CORRECT ANSWERS
Which pairing of an intravenously administered fluid and its effect on both intravascular
fluid volume (IV) and extracellular fluid volume (ECV) would be correct in a normal
patient?
Tonicity is given relative to normal plasma. Assume a simple 2-compartment model
(vascular space [blood/plasma] and extracellular fluid space). - ANSWER- Isotonic
(normal) saline; increase in IV; no change in ECV
A 55-year-old man with a longstanding history of alcoholism is found in a coma following
ingestion of an unknown substance. Lab results show BUN of 11 mg/dL, serum sodium
of 110 mEq/L, and blood glucose of 70 mg/dL, but serum osmolality of 450 mOsm/L.
What finding is most expected - ANSWER- Coma resulted from ingesting a high
osmolarity substance.
What substance readily diffuses across the cell membrane without facilitation? -
ANSWER- Carbon dioxide
What differentiates osmosis from diffusion? - ANSWER- Osmosis seeks to equalize the
concentration of solvent.
What substance uses osmosis to cross the cell membrane? - ANSWER- Water
Diffusion is a mechanism by which molecules are transported across the cell
membrane. Several factors can affect the rate of diffusion. Which description accurately
explains one of these factors? - ANSWER- Higher temperature increases the rate of
diffusion.
What is the most common extracellular cation in the human body? - ANSWER- NA+
(Sodium)
is the most abundant extracellular anion - ANSWER- Chloride
When a neuron begins the process of depolarization, what ion's concentration begins to
rapidly increase within the neuron cell membrane? - ANSWER- The action potential
begins with depolarization. This occurs when sodium ions rapidly flow into the nerve cell
through
What substance is most often transported through the cell membrane via active
transport? - ANSWER- Potassium
, What electrical signal unique to muscle and nerve cells is created by a change in
voltage across the cell membrane? - ANSWER- Action potential
How does a severely low serum potassium affect the cardiac action potential? -
ANSWER- Repolarization time is prolonged.
Which process triggers an action potential? - ANSWER- Depolarization of the
membrane
Action potentials occur in excitable cells (neurons, muscle cells), allowing charged
particles to pass through a channel into the cell membrane. What type of ion channel is
primarily associated with somatosensation? - ANSWER- Mechanically-gated channel
What structure in the cell membrane contributes most to the hydrophilic outer aspect
and hydrophobic inner aspect of the membrane? - ANSWER- Phospholipids
What type of integral protein in the cell membrane is used to pass ions from one side of
the cell membrane to the other? - ANSWER- Channel protein
What component of the phospholipid layer is most responsible for the hydrophilicity of
the molecule? - ANSWER- Phosphate
If the nervous system is suddenly stimulated by a perceived threat, what change causes
an increase in arterial pressure? - ANSWER- Blood volume becomes increased in all
chambers.
A patient has a systolic blood pressure of 120 mm Hg and a diastolic blood pressure of
70 mm Hg. What is this patient's pulse pressure? - ANSWER- 50 mm Hg
Arteriosclerosis, a leading cause of hypertension, affects which variable that influences
blood pressure and blood flow? - ANSWER- Compliance
Which vessel is the first to branch off of the aorta, carrying oxygenated blood into
systemic circulation? - ANSWER- Coronary artery
What component of the circulatory system carries oxygenated blood from the lungs into
the heart? - ANSWER- Pulmonary vein
The vessels in the body are divided into two divisions according to the type of blood
they carry. How do arteries differ from veins? - ANSWER- Arteries have thicker and
more elastic walls.
Unlike most arteries, the pulmonary arteries do not carry oxygenated blood from the
heart to the tissues. What other artery shares this characteristic? - ANSWER- Umbilical
arteries
QUESTIONS WITH CORRECT ANSWERS
Which pairing of an intravenously administered fluid and its effect on both intravascular
fluid volume (IV) and extracellular fluid volume (ECV) would be correct in a normal
patient?
Tonicity is given relative to normal plasma. Assume a simple 2-compartment model
(vascular space [blood/plasma] and extracellular fluid space). - ANSWER- Isotonic
(normal) saline; increase in IV; no change in ECV
A 55-year-old man with a longstanding history of alcoholism is found in a coma following
ingestion of an unknown substance. Lab results show BUN of 11 mg/dL, serum sodium
of 110 mEq/L, and blood glucose of 70 mg/dL, but serum osmolality of 450 mOsm/L.
What finding is most expected - ANSWER- Coma resulted from ingesting a high
osmolarity substance.
What substance readily diffuses across the cell membrane without facilitation? -
ANSWER- Carbon dioxide
What differentiates osmosis from diffusion? - ANSWER- Osmosis seeks to equalize the
concentration of solvent.
What substance uses osmosis to cross the cell membrane? - ANSWER- Water
Diffusion is a mechanism by which molecules are transported across the cell
membrane. Several factors can affect the rate of diffusion. Which description accurately
explains one of these factors? - ANSWER- Higher temperature increases the rate of
diffusion.
What is the most common extracellular cation in the human body? - ANSWER- NA+
(Sodium)
is the most abundant extracellular anion - ANSWER- Chloride
When a neuron begins the process of depolarization, what ion's concentration begins to
rapidly increase within the neuron cell membrane? - ANSWER- The action potential
begins with depolarization. This occurs when sodium ions rapidly flow into the nerve cell
through
What substance is most often transported through the cell membrane via active
transport? - ANSWER- Potassium
, What electrical signal unique to muscle and nerve cells is created by a change in
voltage across the cell membrane? - ANSWER- Action potential
How does a severely low serum potassium affect the cardiac action potential? -
ANSWER- Repolarization time is prolonged.
Which process triggers an action potential? - ANSWER- Depolarization of the
membrane
Action potentials occur in excitable cells (neurons, muscle cells), allowing charged
particles to pass through a channel into the cell membrane. What type of ion channel is
primarily associated with somatosensation? - ANSWER- Mechanically-gated channel
What structure in the cell membrane contributes most to the hydrophilic outer aspect
and hydrophobic inner aspect of the membrane? - ANSWER- Phospholipids
What type of integral protein in the cell membrane is used to pass ions from one side of
the cell membrane to the other? - ANSWER- Channel protein
What component of the phospholipid layer is most responsible for the hydrophilicity of
the molecule? - ANSWER- Phosphate
If the nervous system is suddenly stimulated by a perceived threat, what change causes
an increase in arterial pressure? - ANSWER- Blood volume becomes increased in all
chambers.
A patient has a systolic blood pressure of 120 mm Hg and a diastolic blood pressure of
70 mm Hg. What is this patient's pulse pressure? - ANSWER- 50 mm Hg
Arteriosclerosis, a leading cause of hypertension, affects which variable that influences
blood pressure and blood flow? - ANSWER- Compliance
Which vessel is the first to branch off of the aorta, carrying oxygenated blood into
systemic circulation? - ANSWER- Coronary artery
What component of the circulatory system carries oxygenated blood from the lungs into
the heart? - ANSWER- Pulmonary vein
The vessels in the body are divided into two divisions according to the type of blood
they carry. How do arteries differ from veins? - ANSWER- Arteries have thicker and
more elastic walls.
Unlike most arteries, the pulmonary arteries do not carry oxygenated blood from the
heart to the tissues. What other artery shares this characteristic? - ANSWER- Umbilical
arteries
