Question 1

Oxygenated blood is transported from the lungs through the pulmonary veins into the

Accepted Answer

Oxygenated blood is transported from the lungs through the pulmonary veins into the left atrium.

Question 2

The blood vessel that collects deoxygenated blood from the coronary circulation and delivers it to the right atrium is the

Accepted Answer

The coronary sinus is the blood vessel that collects deoxygenated blood from the coronary circulation and delivers it to the right atrium. The vena cava brings deoxygenated blood from the systemic circulation to the right atrium, but it does not specifically collect blood from the coronary circulation. The sigmoid sinus and pulmonary sinus are not involved in the collection of blood from the coronary circulation. The coronary artery delivers oxygenated blood to the heart muscle, but it does not collect deoxygenated blood.

Question 3

The P wave of an ECG is created by the electrical activity associated with

Accepted Answer

The P wave of an ECG is created by the electrical activity associated with atrial depolarization.

Question 4

Death of an area of cardiac muscle tissue due to an interrupted blood supply is called

Accepted Answer

Death of an area of cardiac muscle tissue due to an interrupted blood supply is called myocardial infarction. Ischemia refers to a decrease in blood flow to a tissue, which can lead to infarction if not resolved. Angina pectoris is chest pain or discomfort that occurs when the heart muscle doesn't get enough oxygen-rich blood. Ventricular fibrillation is an abnormal heart rhythm that can be life-threatening. Myocardial ischemia is a decrease in blood flow to the heart muscle, which can lead to angina or myocardial infarction if not resolved.

Question 5

Which of the following represents the correct sequence of structures in the cardiac action potential conduction system?

Accepted Answer

The correct sequence of structures in the cardiac action potential conduction system starts with the sinoatrial (SA) node, followed by the atrioventricular (AV) node, then the bundle of His, which divides into the right and left bundle branches, and finally ends with the Purkinje fibers.

Question 6

At a normal resting heart rate, the last 25% of the blood that fills the ventricles enters during

Accepted Answer

The last 25% of the blood that fills the ventricles enters during atrial systole. This is when the atria contract, pushing the remaining blood into the ventricles right before the ventricles contract.

Question 7

Oxygenated blood is delivered to the myocardium of the heart by the

Accepted Answer

Oxygenated blood is delivered to the myocardium of the heart by the coronary arteries. The other choices listed are incorrect because they deliver blood to other areas of the body such as the aortic arch delivering blood to the rest of the body, the descending aorta delivering blood to the lower parts of the body, the pulmonary arteries delivering deoxygenated blood to the lungs, and the coronary sinus draining deoxygenated blood from the heart.

Question 8

Which labeled structure in the heart wall diagram is responsible for the pumping action of the heart?

Accepted Answer

The answer of Which labeled structure in the heart wall...

Question 9

The heart valve found between the left atrium and left ventricle is the

Accepted Answer

The bicuspid valve, also known as the mitral valve, is located between the left atrium and left ventricle, and prevents backflow of blood from the left ventricle to the left atrium during ventricular systole. The tricuspid valve is located between the right atrium and right ventricle, while the aortic and pulmonary semilunar valves are found in the arteries leaving the heart. The sinoatrial valve does not exist.

Question 10

The left ventricle pumps blood directly into the

Accepted Answer

The left ventricle is responsible for pumping oxygenated blood out of the heart and into the systemic circulation. This is accomplished by the blood flowing out of the left ventricle and into the ascending aorta.

Question 11

Which of the following lists the correct sequence of waves that occur in an ECG of a single heartbeat?

Accepted Answer

The correct sequence of waves in an ECG for a single heartbeat is P wave, followed by the QRS complex, and then the T wave. The P wave represents atrial depolarization, the QRS complex represents ventricular depolarization, and the T wave represents ventricular repolarization.

Question 12

Which of the following blood vessels delivers deoxygenated blood to the right atrium?

Accepted Answer

The vena cavae are large veins that carry deoxygenated blood from the body back to the heart, specifically to the right atrium.

Question 13

In an ECG, atrial repolarization is indicated by

Accepted Answer

Atrial repolarization is actually masked by the larger electrical activity of ventricular depolarization and does not have a distinct wave or segment on the ECG that is specifically designated for it. The P wave represents atrial depolarization, the QRS complex represents ventricular depolarization, and the T wave represents ventricular repolarization.

Question 14

The muscular wall of the left ventricle is thicker than the right ventricle because it

Accepted Answer

The left ventricle has a thicker muscular wall because it needs to generate a higher pressure to pump blood throughout the entire body, as opposed to the right ventricle, which only pumps blood to the lungs.

Question 15

The heart valve found between the left ventricle and the large artery exiting the left ventricle is the

Accepted Answer

The valve found between the left ventricle and the large artery exiting the left ventricle is the aortic valve.

Question 16

Which of the following vessels carries blood with the highest concentration of oxygen under normal conditions?

Accepted Answer

The pulmonary veins carry freshly oxygenated blood from the lungs to the left atrium, which then pumps the oxygen-rich blood out to the rest of the body, making it the vessel with the highest concentration of oxygen under normal conditions.

Question 17

In the diagram, where is the auricle of left atrium?

Accepted Answer

The answer of In the diagram, where is the auricle...

Question 18

At a normal resting heart rate, each cardiac cycle lasts approximately

Accepted Answer

At a normal resting heart rate, which is typically around 60 to 100 beats per minute, each cardiac cycle lasts approximately 0.8 seconds. This duration encompasses all phases of the cardiac cycle, including atrial and ventricular systole and diastole.

Question 19

Which of the following chambers of the heart has the thickest myocardium?

Accepted Answer

The left ventricle has the thickest myocardium because it is responsible for pumping oxygenated blood to the entire body, thus requiring more forceful contractions than the other chambers.

Question 20

The normal pacemaker of the heart is the

Accepted Answer

The sinoatrial (SA) node is known as the normal pacemaker of the heart. It is located in the right atrium and initiates the electrical impulses that cause the heart to beat at a regular rate.

Quiz 15: The Cardiovascular System: Heart