Mastering A&P 18

Into which chamber of the heart do the superior vena cava, inferior vena cava, and coronary sinus return deoxygenated blood? left ventricle right atrium left atrium right ventricle

The right side of the heart is considered the systemic circuit pump. True False

Cardiac tamponade results in ineffective pumping of blood by the heart because the excessive amount of fluid in the pericardial cavity will______. prevent the visceral layer of the serous pericardium from properly surrounding the heart prevent the heart from filling properly with blood prevent proper oxygenation of the blood interfere with the ability of this fluid to lubricate the serous membranes

What causes heart sounds? heart valve closure blood flowing from the atria into the ventricles pressure of blood in the ventricles opening of heart valves

The myocardium receives its blood supply from the coronary arteries. True False

What structures connect the individual heart muscle cells? trabaculae carneae chordae tendineae anastomoses intercalated discs

Isovolumetric relaxation and ventricular filling (two phases of the cardiac cycle) take place during __________. ventricular diastole ventricular systole

Describe the pressures in the atria and ventricles that would cause the opening of the AV valves. Pressure in the ventricles would be greater than in the atria. Pressures in the atria and ventricles would be equal. Pressure in the atria would be greater than the pressure in the ventricles.

What causes the aortic semilunar valve to close? greater pressure in the aorta than in the left ventricle higher ventricular pressure than aortic pressure equal ventricular and aortic pressures

Increased pressure in the ventricles would close what valve(s)? semilunar valves only both semilunar and AV valves AV valves only

In what direction does blood flow through the heart? from a region of high volume to a region of low volume from a region of high oxygen content to a region of low oxygen content from ventricles to atria from a region of high pressure to a region of low pressure

Atrial pressure is greater than ventricular pressure during which phase of the cardiac cycle? isovolumetric relaxation atrial contraction ventricular ejection isovolumetric contraction

At what point during the cardiac cycle does the AV valve close? View Available Hint(s) when the semilunar valve opens when ventricular pressure becomes greater than atrial pressure when aortic pressure becomes greater than ventricular pressure when ventricular pressure becomes greater than aortic pressure

At what point in the cardiac cycle does the semilunar valve open? when the AV valve closes when atrial pressure becomes greater than ventricular pressure when ventricular pressure becomes greater than aortic pressure when ventricular pressure becomes greater than atrial pressure

Ventricular pressure is greater than aortic pressure during which phase of the cardiac cycle? ventricular filling isovolumetric contraction isovolumetric relaxation ventricular ejection

Isovolumetric relaxation is characterized by which of the following? Pressure in the ventricle exceeds pressure in the aorta. Pressure in the atrium exceeds pressure in the ventricle. Blood flows backward through the heart from high to low pressure. The semilunar and AV valves are closed.

At what point in the cardiac cycle does the AV valve open? when the semilunar valve closes when ventricular pressure becomes greater than aortic pressure when atrial pressure becomes greater than ventricular pressure when aortic pressure becomes greater than ventricular pressure P

Which portion of the electrocardiogram represents the depolarization wave received by the atria from the sinoatrial (SA) node? T wave S-T segment P wave QRS complex

What is the period during the cardiac cycle when the ventricles are completely closed and blood volume in them remains constant as the ventricles contract? ventricular filling ventricular ejection isovolumetric contraction phase isovolumetric relaxation phase

Which of the following increases stroke volume? decrease in preload decrease in end diastolic volume (EDV) exercise severe blood loss

Which of these is a condition marked by premature ventricular contraction? ectopic focus heart block extrasystole arrhythmia

The P wave on an electrocardiogram represents __________. ventricular repolarization ventricular depolarization atrial repolarization atrial depolarization

What best describes afterload? cardiac reserve contractility of cardiac muscle back pressure exerted by arterial blood degree of stretch of the heart muscle

The second heart sound is heard during which phase of the cardiac cycle? ventricular filling isovolumetric relaxation ventricular ejection isovolumetric contraction

As pressure in the aorta rises due to atherosclerosis, more ventricular pressure is required to open the aortic valve. True False

The _____________ carries oxygen-poor venous blood from above the diaphragm from areas of the upper body and extremities into the right atrium.

The ______ carries oxygen-poor venous blood of the coronary circulation into the right atrium.

The ___________ carries oxygen-poor venous blood from below the diaphragm from the areas of the lower body and extremities into the right atrium.

Which part of the intrinsic conduction system normally initiates the depolarizing impulse that causes a heartbeat? View Available Hint(s) AV bundle Internodal pathway AV node SA node

At what point in the cardiac cycle is pressure in the ventricles the highest (around 120 mm Hg in the left ventricle)? mid-to-late diastole (ventricular filling) ventricular systole early diastole (isovolumetric relaxation) mid-to-late diastole (atrial contraction)

Which best describe the isovolumetric contraction phase of the cardiac cycle? As ventricular systole start, the AV valves are closed and the semilunar valves are closed. Because the ventricles are contracting and both valves are closed, pressure increases rapidly leading to ejection. As pressure builds up in the ventricles during systole, the AV valves open and allow blood to leave the heart. As ventricular systole starts, the AV valves close, which immediately opens the semilunar valves. The pressure from the atrial contractions opens the semilunar valves.

As your muscles contract during activity, more blood is returned to the heart. Which variable would be affected and what would be the outcome of this action? End-systolic volume would be increased, which would increase cardiac output. Preload would be increased, which would increase cardiac output. Contractility would be increased, which would increase cardiac output. Afterload would increase, which would increase cardiac output.

Which chamber of the heart has the highest probability of being the site of a myocardial infarction? left atrium right atrium left ventricle right ventricle

Select the correct statement about the heart valves. The tricuspid valve divides the left atrium from the left ventricle. Aortic and pulmonary semilunar valves control the flow of blood into the heart. The atrioventricular (AV) valves prevent backflow of blood into the atria during ventricular contraction. The mitral (bicuspid) valve separates the right atrium from the right ventricle.

The left side of the heart pumps the same volume of blood as the right. True False

If the aorta and pulmonary trunk were switched, oxygen rich blood would be pumped from the left ventricle to the lungs. True False