Chapter 18 The Heart Flashcards
heart muscle is deprived of oxygen
ischemia
death of heart muscle cells
infarction
a condition of rapid and irregular or out of phase contraction of ventricular heart muscle cells
fibrillation
an abnormal pacemaker
ectopic focus
total heart relaxation
quiescent period
The myocardium receives its blood supply from the coronary arteries
true
cardiac muscle has more mitochondria and depends less on a continual supply of oxygen than does skeletal muscle
False; depends more on a continual supply of oxygen (I think)
anastomoses among coronary arterial branches provide collateral routes for blood delivery to the heart muscle
true
if blood volume decreased dramatically due to massive bleeding, the autonomic nervous system will attempt to maintain cardiac output by increasing the heart rate
true
tissues damaged by myocardial infarction are replaced by fibrous connective tissue
true
the left side of the heart pumps the same volume as the right
true
when released in large quantities, thyroxine causes a sustained increased heart rate
true
arterial blood supply to heart muscle is continuous whether the heart is in systole or diastole
false; coronary arteries not arterial
auricles slightly increase blood volume in the ventricles
true
the lub sounds of the heart are valuable in diagnosis because they provide information about the function of the heart’s pulmonary and aortic semilunar valves
false; provide information about the function of the heart’s mitral and tricuspid valves
autonomic regulation of heart rate is via two reflex centers found in the pons
false; found in the medulla
the papillary muscles contract after the other ventricular muscles so that they can take up the slack on the chordae tendineae before the full force of ventricular contractions sends blood against the AV valve flaps
false; ??
an ECG provides direct information about valve function
false; electrical activity
as pressure in the aorta and pulmonary trunk were switched, oxygen rich blood would be pumped from the left ventricle to the lungs
true
heart tissue is supplied with nutrients primarily by diffusion from the heart chambers through the myocardium
false; primarily by coronary arteries through to the myocardium???
normal heart sounds are caused by which of the following events?
closure of the heart valves
during the isovolumetric relaxation phase of the cardiac cycle, ______.
atrioventricular, aortic, and pulmonary valves are closed
hemorrhage with a large loss of blood causes ______.
a lowering of blood pressure due to change in cardiac output
the left ventricular wall of the heart is thicker than the right wall in order to _______.
pump blood with greater pressure
which chambers of the heart contain oxygenated blood?
left atrium and ventricle
if the SA node is not functioning, an ECG will show __________.
no P waves with a HR between 40-60
The receiving chambers of the heart include the ________.
right and left atria
the condition where fluid compresses the heart and limits its ability to contract is called _______.
cardiac tamponade
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
to auscultate the aortic semilunar valve, you would place your stethoscope in the ______.
second intercostal space to the right of the sternum
the source of blood carried to capillaries in the myocardium would be the ______.
coronary arteries
the fact that the left ventricle to the heart is thicker than the right ventricle reveals that it _______.
pumps blood against a greater resistance
the parietal pericardium _________.
lines the internal surface of the fibrous pericardium