Ch. 18: The Heart

The AV valve with three flaps is the _________.

right AV valve

Which chamber of the heart does the coronary sinus deliver blood into?

right atrium

The refractory period in cardiac muscle is very long to prevent the possibility of _________, a condition in which muscle locks up or remains in contraction.

tetany

Which of the events below does not occur when the semilunar valves are open? Ventricles are in systole (contraction). Blood enters pulmonary arteries and the aorta. AV valves are closed. Ventricles are in diastole (relaxation).

ventricles are in diastole (relaxation).

Which phase of the Cardiac Cycle opens the semilunar valves?

ventricular ejection

Which of the following would cause an increase in the heart rate? an increase in the pH of the blood a decreased in the H+ concentration of the blood an increased O2 concentration of the blood an increased CO2 concentration of the blood

an increased CO2 concentration of the blood

In the case of an acute myocardial infarction, the term for sudden pain beneath the sternum that commonly radiates down the left arm in males, but not in females is ________.

angina pectoris

Which valve prevents backflow into the left ventricle?

aortic valve

The SA node, without nervous or endocrine control, would initiate a heart rate of approximately _________ bpm (beats per minute).

80-100 bpm

Which portion of the Cardiac Conduction System carries the impulse into the interventricular septum?

AV bundle (Bundle of His)

During which phase of the Cardiac Cycle are the atria pushing the last 20% of blood into the ventricles?

Atrial Systole (contraction)

T/F: An ECG provides direct information about valve function.

F

T/F: Autonomic regulation of heart rate involves reflex centers found in the cerebral cortex.

F

T/F: The "lub" or first heart sounds are valuable in diagnosis because they provide information about the function of the pulmonary and aortic valves.

F

Which phase of the Cardiac Cycle closes the AV valves?

Isovolumetric Ventricular Contraction

At which point in the Cardiac Cycle are all chambers relaxed and all valves closed?

Isovolumetric Ventricular Relaxation

AV valve with two flaps.

Mitral (bicuspid) valve

Which part of the cardiac conduction system directly stimulates the ventricular muscle cells to contract?

Purkinje fibers

The pacemaker of the heart is the ___________________.

SA Node

T/F: A murmur is an abnormal heart sound that can be detected via auscultation.

T

T/F: As pressure in the aorta rises due to conditions such as atherosclerosis, the ventricle must contract with more force to create the additional pressure needed to open the aortic valve.

T

T/F: Congestive heart failure means that the pumping efficiency of the heart is depressed so that there is inadequate delivery of blood to body tissues.

T

T/F: The myocardium (composed of cardiomyocytes) receives its blood supply from branches of the coronary arteries.

T

T/F: The papillary muscles contract in order to take up the slack on the chordae tendineae before the full force of ventricular contractions sends blood upward, closing the flaps of the AV valves.

T

T/F: The pulmonary semilunar valve is the anterior most valve within the human heart.

T

T/F: The right side of the heart pumps blood to the lungs.

T

T/F: Tissues damaged by a myocardial infarction are eventually replaced by connective tissue and cannot contract.

T

What is the scientific term for the ability to stretch and recoil within an artery?

compliance

Select the correct statement about the structure of the heart wall. The fibrous cardiac skeleton forms most of the tissue of the heart. The heart chambers are lined (on the inside) by the endocardium. The myocardium is the thinnest layer of the heart wall. Connective tissue in the heart wall aids in the conduction of the action potential.

The heart chambers are lined (on the inside) by the endocardium.

Starling's law of the heart ensures that______________________.

The volume of blood that enters the heart equals the volume that exits the heart.

The atrioventricular bundle is also known as the _________.

bundle of his

The left ventricular wall of the heart is thicker than the right ventricular wall in order to ________.

adequately serve systemic circulation

The force the ventricles must develop or overcome to effectively pump blood against the resistance within the blood vessels is termed _________.

afterload

The P wave of an electrocardiogram represents which electrical event?

atrial depolarization

Which part of the cardiac conduction system temporarily delays the impulse?

av node

During the period of ventricular filling ________.

blood flows passively through the atria and the AV valves into the ventricles

Sympathetic control of the heart involves which nerves?

cadiac nerves (T1-t5)

During the plateau phase ________.

calcium enters the cardiac muscle cells

Normal heart sounds are caused by which of the following events?

closure of the heart valves

If cardiac muscle is deprived of its normal blood supply, damage to the muscle tissue of the heart would primarily result from ________.

decreased levels of oxygen (hypoxia)

Which term describes an area other than the SA node generating an impulse that leads to a premature contraction?

ectopic focus

During which phase of the Cardiac Cycle is blood leaving the ventricles?

ejection

Which is the correct term for the inner lining of the heart?

endocardium

The outer layer of the heart is a serous layer that is separated from the partietal pericardium by small space and pericardial fluid. Which of the following is one of the names for the outer layer of the heart?

epicardium

Wild and uncontrolled contractions of the heart, which prevent the heart from pumping effectively is known as __________________.

fibrillation

Compared to skeletal muscle, cardiac muscle ________.

has gap junctions and branching of the cells that allow cardiac muscle to function as a unit or syncytium

An interruption to the normal conduction pathway leads to a condition known as _________.

heart block

Which terms refers to a decrease in blood flow to an area of tissue, such as the heart muscle?

ischemia

Blood within the pulmonary veins is flowing toward which chamber of the heart.

left atrium

Hemorrhage with a large loss of blood causes ________.

lowering of BP

The time of day most hazardous for heart attacks is ________.

morning

A __________ refers to death of heart muscle cells.

myocardial infarction

Which term refers to the muscle of the heart?

myocardium

The chordae tendineae are directly attached to which muscular structures?

papillary muscles

The outermost layer of the serous pericardium is called the _________________.

parietal layer

Blood enters the right atrium as it leaves which vessels?

vena cavae

The tricuspid valve closes when ________.

the ventricle is contracting

Which heart valves prevents backflow into the right atrium?

tricuspid valve

Which valve prevents backflow into the right atrium?

tricuspid valve