NURS5315 EXAM QUESTIONS
AND ANSWERS – 2025 EDITION
What are the two major coronary arteries? (Book) - Answer-The major coronary arteries
are the right coronary artery (RCA) and the left coronary artery (LCA)
The transmission of electrical impulses, termed cardiac action potentials move
throughout the myocardium. Analyze the process of action potentials. (Book) - Answer-
As an electrical impulse passes from cell to cell (fiber to fiber) in the myocardium, it
stimulates an intracellular process that results in fiber shortening—that is, muscular
contraction or systole. Between action potentials, the fibers relax and return to their
resting length, causing diastole.
The various phases of the cardiac action potential are related
to changes in the permeability of the cell membrane to sodium,
potassium, chloride, and calcium(Book) - Answer-Threshold is the point at which the
cell membrane's selective permeability to these ions is temporarily disrupted, leading to
depolarization. If the resting membrane potential becomes more negative as a result of
a decrease in extracellular potassium concentration (hypokalemia), it is termed
hyperpolarization.
How potassium affects myocardial action potentials, contraction, and clinical
manifestations.
Hypokalemia - Answer-When the resting membrane potential becomes more negative
as a result of a decrease in extracellular potassium concentration (Book)
it is termed hyper-polarization.
Left Heart (book) - Answer-sends blood throughout the systemic circulation, which
supplies all of the body except the lungs.
Arteries (hint A for away) (Book) - Answer-carry blood (away) from the heart to all parts
of the body, where they branch into arterioles and even smaller vessels until they
become a fine meshwork of capillaries.
Capillaries (Book) - Answer-allow the closest contact and exchange between the blood
and the interstitial space, or interstitium—the environment in which the cells live
Venules and the veins (Book) - Answer-carry blood from capillaries back to the heart.
Lymph (Book) - Answer-is returned to the cardiovascular system by vessels of the
lymphatic system.
, Calcium and Excitation-contraction coupling is the process by which an action potential
arriving at the plasma membrane of the muscle fiber triggers the cycle leading to cross-
bridge activity and contraction. (Book) - Answer-It enters the myocardial cell from the
interstitial fluid after electrical excitation, which increases the membrane permeability to
calcium. Two types of calcium channels (L-type and T-type) are identified in cardiac
tissues.
Calcium interacts with troponin C which causes tropomyosin to move thus allowing actin
and myosin to work together to cause contraction. (Lecture) - Answer-The greater the
amount of intracellular calcium the stronger the contraction.
Hypercalcemia - Answer-Because serum calcium levels are increased, a greater
amount of calcium is also contained inside the cells. The threshold potential becomes
more positive (hyperpolarized) (e.g., moves from −60 to −50 millivolts) and the cell
membrane becomes refractory to depolarization (decreased excitability).
Hypocalcemia manifestations - Answer-there is an increase in neuromuscular
excitability
Hypocalemia manifestations - Answer-Two clinical signs are Chvostek sign and
Trousseau sign. Chvostek sign is elicited by tapping on the facial nerve just below the
temple. A positive sign is a twitch of the nose or lip. Trousseau sign is contraction of the
hand and fingers when the arterial blood flow in the arm is occluded for 5 minutes with
the use of a blood pressure cuff. More severe forms manifest tetany.
Myocardial relaxation (Lecture) - Answer-intracellular calcium levels decrease.
Magnesium is required for (Book) - Answer-the binding of ATP to the myosin site.
Hypomagnesaemia: (Book) - Answer-clinical manifestations include behavioral
changes, irritability, increased reflexes, muscle cramps, ataxia, nystagmus, tetany,
convulsions, tachycardia, hypotension. Because magnesium inhibits potassium
channels, loss of magnesium results in movement of potassium out of the cell, with
renal excretion resulting in hypokalemia.
What are the implications for calcium channel blockers? (book) - Answer-HTN
Digitalis overdose (book) - Answer-may cause hyperkalemia by inhibiting the Na+-K+
ATPase pump. This pump normally maintains intracellular K+ concentration and moves
sodium and calcium to the ECF. Treated with digoxin immune fab (internet).
Dobutamine (lectures) - Answer-Dobutamine stimulates the beta 1 receptors in the
myocardium and improves contractility and increases heart rate.
Increase contractility and can help raise the blood pressure (Book)
Implication for dobutamine ? (book) - Answer-hypo-tension, acute onset of left heart
failure which is often the result of acute myocardial ischemia and must be managed in
conjunction with the underlying coronary disease
AND ANSWERS – 2025 EDITION
What are the two major coronary arteries? (Book) - Answer-The major coronary arteries
are the right coronary artery (RCA) and the left coronary artery (LCA)
The transmission of electrical impulses, termed cardiac action potentials move
throughout the myocardium. Analyze the process of action potentials. (Book) - Answer-
As an electrical impulse passes from cell to cell (fiber to fiber) in the myocardium, it
stimulates an intracellular process that results in fiber shortening—that is, muscular
contraction or systole. Between action potentials, the fibers relax and return to their
resting length, causing diastole.
The various phases of the cardiac action potential are related
to changes in the permeability of the cell membrane to sodium,
potassium, chloride, and calcium(Book) - Answer-Threshold is the point at which the
cell membrane's selective permeability to these ions is temporarily disrupted, leading to
depolarization. If the resting membrane potential becomes more negative as a result of
a decrease in extracellular potassium concentration (hypokalemia), it is termed
hyperpolarization.
How potassium affects myocardial action potentials, contraction, and clinical
manifestations.
Hypokalemia - Answer-When the resting membrane potential becomes more negative
as a result of a decrease in extracellular potassium concentration (Book)
it is termed hyper-polarization.
Left Heart (book) - Answer-sends blood throughout the systemic circulation, which
supplies all of the body except the lungs.
Arteries (hint A for away) (Book) - Answer-carry blood (away) from the heart to all parts
of the body, where they branch into arterioles and even smaller vessels until they
become a fine meshwork of capillaries.
Capillaries (Book) - Answer-allow the closest contact and exchange between the blood
and the interstitial space, or interstitium—the environment in which the cells live
Venules and the veins (Book) - Answer-carry blood from capillaries back to the heart.
Lymph (Book) - Answer-is returned to the cardiovascular system by vessels of the
lymphatic system.
, Calcium and Excitation-contraction coupling is the process by which an action potential
arriving at the plasma membrane of the muscle fiber triggers the cycle leading to cross-
bridge activity and contraction. (Book) - Answer-It enters the myocardial cell from the
interstitial fluid after electrical excitation, which increases the membrane permeability to
calcium. Two types of calcium channels (L-type and T-type) are identified in cardiac
tissues.
Calcium interacts with troponin C which causes tropomyosin to move thus allowing actin
and myosin to work together to cause contraction. (Lecture) - Answer-The greater the
amount of intracellular calcium the stronger the contraction.
Hypercalcemia - Answer-Because serum calcium levels are increased, a greater
amount of calcium is also contained inside the cells. The threshold potential becomes
more positive (hyperpolarized) (e.g., moves from −60 to −50 millivolts) and the cell
membrane becomes refractory to depolarization (decreased excitability).
Hypocalcemia manifestations - Answer-there is an increase in neuromuscular
excitability
Hypocalemia manifestations - Answer-Two clinical signs are Chvostek sign and
Trousseau sign. Chvostek sign is elicited by tapping on the facial nerve just below the
temple. A positive sign is a twitch of the nose or lip. Trousseau sign is contraction of the
hand and fingers when the arterial blood flow in the arm is occluded for 5 minutes with
the use of a blood pressure cuff. More severe forms manifest tetany.
Myocardial relaxation (Lecture) - Answer-intracellular calcium levels decrease.
Magnesium is required for (Book) - Answer-the binding of ATP to the myosin site.
Hypomagnesaemia: (Book) - Answer-clinical manifestations include behavioral
changes, irritability, increased reflexes, muscle cramps, ataxia, nystagmus, tetany,
convulsions, tachycardia, hypotension. Because magnesium inhibits potassium
channels, loss of magnesium results in movement of potassium out of the cell, with
renal excretion resulting in hypokalemia.
What are the implications for calcium channel blockers? (book) - Answer-HTN
Digitalis overdose (book) - Answer-may cause hyperkalemia by inhibiting the Na+-K+
ATPase pump. This pump normally maintains intracellular K+ concentration and moves
sodium and calcium to the ECF. Treated with digoxin immune fab (internet).
Dobutamine (lectures) - Answer-Dobutamine stimulates the beta 1 receptors in the
myocardium and improves contractility and increases heart rate.
Increase contractility and can help raise the blood pressure (Book)
Implication for dobutamine ? (book) - Answer-hypo-tension, acute onset of left heart
failure which is often the result of acute myocardial ischemia and must be managed in
conjunction with the underlying coronary disease
