Ch 18 - The Heart Flashcards
Heart muscle
Myocardium
Serous layer covering the heart muscle
Epicardium
The outermost layer of the serous pericardium
Parietal layer
SA node
Pacemaker of the heart
Found in the interventricular septum
AV bundle
Network found in the ventricular myocardium
Purkinje fibers
The point in the conduction system of the heart where the impulse is delayed
AV node
Prevents backflow into the left ventricle
Aortic valve
Prevents backflow into the right atrium
Tricuspid valve
Prevents backflow into the left atrium
Bicuspid valve
Prevents backflow into the right ventricle
Pulmonary valves
AV valve with 2 flaps
Bicuspid valve
AV valve with 3 flaps
Tricuspid valve
True or false? The myocardium receives its blood supply from the coronary arteries.
True
True or false? Cardiac muscle has more mitochondria and depends less on a continual supply of oxygen than does skeletal muscle.
False
Endocardium
The inner lining of the heart
True or false? Proper function of the heart is dependent upon blood levels of ionic sodium
False
True or false? Congestive heart failure means that the pumping efficiency of the heart is depressed so that there is inadequate delivery of blood to body tissues
True
True or false? Tissues damaged by myocardial infarction (heart attack) are replaced by connective tissue
True
True or false? The left side of the heart pumps the same volume of blood as the right
True
True or false? Chronic release of excess thyroxine can cause a sustained increase in heart rate and a weakened heart
True
True or false? The mitral valve has chordae but the tricuspid valve does not
False
True or false? Trabeculae carneae are found in the ventricles and never the atria
True
True or false? The “lub” sounds of the heart are valuable in diagnosis because they provide information about the function of the heart’s pulmonary and aortic valves
False
True or false? Autonomic regulation of heart rate is via 2 reflex centers found in the pons
False
True or false? The dicrotic notch refers to the brief rise in pressure caused by the closure of the AV valves during ventricular systole
False
True or false? An ECG provides direct information about valve function
False
True or false? As pressure in the aorta rises due to atherosclerosis, more ventricular pressure is required to open the aortic valve
True
True or false? Proxysmal atrial tachycardia is characterized by bursts of atrial contractions with little pause between them
True
Normal heart sounds are caused by _______________.
Closure of the heart valves
Cardiac reserve can be improved by ______________________.
Regular exercise
Hemorrhage with a large loss of blood causes _______________________ due to change in cardiac output
A lowering of blood pressure
The left ventricular wall of the heart is thicker than the right wall in order to do what?
Pump blood with greater pressure
Damage to the __________ is referred to as heart block
AV node
The P wave of a normal electrocardiogram indicates what?
Atrial depolarization
Blood within the pulmonary veins returns to the ___________________
Left atrium
Small muscle masses attached to the chordae tendineae are the ________________________
Papillary muscles
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 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
When the heart is beating at a rate of 75 times per minute, the duration of one cardiac cycle is _______ seconds.
0.8