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.