The pace maker of the heart?
SA node
Found in the inter ventricular septum?
AV bundle
Network found in the ventricular myocardium?
Purine fibers
The point in the conduction system of the heart were the impulse is temporarily delayed?
AV node
Prevents back flow into the left ventricle?
Aortic valve
Prevents flow into the right atrium?
Tricuspid
Prevents back flow into the left atrium?
Mitral valve
Prevents back flow into the right ventricle?
Pulmonary valves
AV valve with two flaps?
Mitral valve
AV valve with three flaps?
Tricuspid valve
Heart muscle is deprived by oxygen?
Ischmia
Deaths of heart muscle cells?
Ectopic focus
A condition of rapid and irregular or out-of-phase contraction of heart muscle cells?
Fibrilation
Total heart relaxation?
Quiescent period
Normal sounds are caused by which of the following events?
Excitation of the SA node
Closure of the heart valves
Friction of blood against the chamber walls
Opening and closing of the heart
Closure of the heart valves
Which of the following events below does not occur when the semilunar valves are open?
Ventricles are in diastole
Blood enters pulmonary arteries and the aorta
AV valves are closed
Ventricles are in systole
Ventricles are in diastole
Hemorrhage with a large loss of blood causes
A lowering of blood pressure due to change in cardiac output
The left ventricle wall of the heart is thicker than the right wall in order to?
Pump blood with greater pressure
Damage to the _________ is referred to as a heart block.
AV node
The P wave of a normal electrocardiogram indicates
Atrial depolorization
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 ausculate 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 of the heart is thicker than the right ventricle reveals that it_________.
Pumps blood against a greater resistance
Which of the following factors does not influence heart rate?
Skin color
Age
Gender
Body temperature
Skin color
Which of the following is NOT an age-related change affecting the heart?
Atherosclerosis
Decline in cardiac reserve
Fibrosis of cardiac muscle
Thinning of the valve flaps
Thinning of the valve flaps
If cardiac muscle is deprived of its normal blood supply, damage would primarily result from _________.
Decreased delivery of oxygen
If the length of the absolute refractory period in cardiac muscle cells was the same as it is for skeletal muscle cells _________.
Titanic contractions might occur ,which would stop the hearts pumping action
Norepinephrine acts on the heart by ________.
Causing threshold to be reached more quickly
If the vagal heart nerves to the heart were cut ,the results would be that ________.
The heart rate would increase by about 25 beats per minute
The foremen ovals connects to _________.
The two atria in the fetal heart
Which vessels of the heart receives blood during right ventricle systole?
Pulmonary trunk
Which of these vessels receives blood during ventricular systole?
Aorta only
Pulmonary arteries only
Pulmonary veins only
Both the aorta and pulmonary trunk
Both the aorta and pulmonary trunk
Which of the following is NOT part of the conduction system of the heart?
AV node
Bundle of his
AV valve
SA node
AV valve
The tricuspid valve is closed when or while ?
When the ventricle I in systole
When viewing a dissected heart , it is easy to visually discern the right and left ventricles by_________.
Noticing the thickness of the ventricle walls
Select the correct statement about the heart valves
The mitral valve separates the right atrium from the right ventricle .
The tricuspid valve devides the left atrium from the left ventricle.
Aortic and pulmonary valves control the flow of blood into the heart.
The AV valves are supported by chordae tendineae so that regurgitation of blood into the atria during ventricular contraction does not occur.
The AV valves are supported by chordae tendineae so that regurgitation of blood into the atria during ventricular contraction does not occur.
Select the CORRECT statement about the function of myocardial cells.
The entire heart contracts as a unit or it does not contract at all.
Each cardiac muscle cell is innervated by a sympathetic nerve ending so that the nervous system can increase heart rate .
The refractory period in skeletal muscle is much longer than that in cardiac muscle.
The influx of potassium ions from extra cellular sources is the initiating event in cardiac muscle contraction.
The entire heart contracts as a unit or it does not contract at all.
Select the correct statement about the structure of the heart wall.
The fibrous skeleton forms the bulk of the heart.
Connective tissue in the heart wall aids in the conduction of the action potential.
The heart chambers are lined by the endomysium .
The myocardium is the layer of the heart that actually contracts.
The myocardium is the layer of the heart that actually contracts.
Compared to skeletal muscle, cardiac muscle ________.
Has gap junctions that allow it to act as a functional syncytium.
During the period of ventricular filling _________.
Blood flows passively through the atria and the open AV valves into the ventricles
The second heart sound is heard during which phase of the cardiac cycle ?
Isovolumetric relaxation
The time of day most hazardous for heart attacks is ___________.
Morning
If we were able to artificially alter the membrane permeability of pacemaker cells So that sodium influx is more rapid,________.
Threshold is reached more quickly and heart rate would increase.
Select the correct statement about cardiac output.
A slow heart rate increases end diastolic volume, stroke volume,and force of contraction.
During contraction of the heart muscle cells ________.
Some calcium enters the cell from the extra cellular space and triggers the release of larger amounts of calcium from intracellular stores.
Isovolumetric contraction ________.
Refers to the short period during ventricular systole when the ventricles are completely closed chambers.
Commotion cordis is heart failure due to a ________.
Relatively mild blow to the chest that occurs during a vulnerable interval(2ms) when the heart is repolarizing .
The enlarged coronary vessel outside the heart that empties blood into the right atrium is the _________.
Coronary sinus
What structure is the fetal heart allows blood to flow from the right atrium directly to the left atrium?
Forman ovale
The ECG T wave interval represents ___________.
Atrial repolarization
CO= _______ x SV.
HR
The _________ membrane cover the heart.
Epicardium
The _________ valve of the heart has three valves with chordae tendinae.
Tricuspid
The _______and________ valves of the heart have NO chordae tendinae attached.
Aortic & Pulmonary
Define systole and diastole?
Systole refers to the periods of contraction ,
Diastole refers to the relaxation and dialation period.