24 terms


What structures connect the individual heart muscle cells?
intercalated discs
When viewing a dissected heart, it is easy to visually discern the right and left ventricles by ________.
noticing the thickness of the ventricle walls
The left ventricular wall of the heart is thicker than the right wall in order to ________.
pump blood with greater pressure
The fact that the left ventricle of the heart is thicker than the right ventricle reveals that it ________.
pumps blood against a greater resistance
The order of impulse conduction in the heart, from beginning to end, is __________.
SA node, AV node, bundle of His, bundle branches, and Purkinje fibers
In a healthy individual which of the following would be low?
Anastomoses among coronary arterial branches provide collateral routes for blood delivery to the heart muscle.
The greater the mass of tissue in an organ, the greater is its need for an adequate blood supply. Which chamber of the heart has the highest probability of being the site of a myocardial infarction?
left ventricle
Hemorrhage with a large loss of blood causes ________.
a lowering of blood pressure due to change in cardiac output
Which of the following does NOT deliver blood to the right atrium?
pulmonary veins
Which of the following increases stroke volume?
The left side of the heart pumps the same volume of blood as the right.
What does the T wave of the electrocardiogram (ECG) represent?
ventricular repolarization
Which of the following structures sets the pace of heart contraction?
SA node
If cardiac muscle is deprived of its normal blood supply, damage would primarily result from ________.
decreased delivery of oxygen
The term for pain associated with deficient blood delivery to the heart that may be caused by the transient spasm of coronary arteries is ________.
angina pectoris
The P wave of a normal electrocardiogram indicates ________.
atrial depolarization
The QRS complex on an electrocardiogram represents __________.
ventricular depolarization
The source of blood carried to capillaries in the myocardium would be the ________.
coronary arteries
At what point in the cardiac cycle is pressure in the ventricles the highest (around 120 mm Hg)?
ventricular systole
Consider the following characteristics of the cells found in muscle tissue. Which feature is shared by both cardiac muscle and skeletal muscle?
The role of the coronary arteries is to __________.
supply blood to the heart tissue
Blood within the pulmonary veins returns to the ________.
left atrium
At what rate does the sinoatrial (SA) node ensure depolarization in the heart?
75 beats of the heart per minute