Week 8: Cardiac Cycle

Select the correct partial path. This path is part of the complete blood flow pathway. You should be able to trace flow starting in any location.

Blood moves from the aorta, through smaller systemic arteries, and into systemic capillaries. From there it moves through systemic veins, into the right atrium, and through the tricuspid valve.

Before Baby A was born, she was not sending much blood to her lungs. Instead, the blood passed through the septal defect into the left atrium, which sent it to the left ventricle and to her body. But why didn't the baby die if no blood was going through her lungs?

She was getting her oxygen from the placenta, not from breathing.

The echocardiogram revealed an atrial septal defect as well as confirming the enlarged right ventricle and pulmonary trunk. Baby A's systemic blood pressure is also decreased.What is the most likely explanation?

Since blood is moving from her systemic circuit into her pulmonary circuit, the pulmonary circuit is distended and the systemic circuit is low on blood.

In Baby A, the atrial septal defect did not close at birth. Blood is flowing through her defect in what direction? Choose the best answer.

from the left atrium into the right atrium The right side of the heart is sending blood to the lungs. The lungs are low pressure, so the right side of the heart is also low pressure. The left side is high pressure.

The heart is actually (one, two, or three) pumps?

two pumps The right side of the heart pumps to/from the lungs (pulmonary circuit) and the left side of the heart pumps to/from the rest of the body (the systemic circuit).

Which heart chamber pumps unoxygenated blood out the pulmonary trunk?

right ventricle

Which heart chamber receives blood from the pulmonary veins?

left atrium

Which chamber pumps oxygenated blood out the aorta to the systemic circuit?

left ventricle

Drag and drop the terms to the appropriate blanks in the sentences on the right. Not all labels are used.

1. The structure that prevents backflow of blood into the left atrium is the mitral (bicuspid) valve. 2. The vessel that carries oxygen-rich blood to tissues is the aorta. 3. The capillaries receiving blood flow from the left side of the heart are the systemic capillaries. 4. The structure that is located anatomically between the aorta and the left ventricle is the aortic semilunar valve.

Baby A was scheduled for surgery to repair her atrial septal defect. The operation went well, and she is recovering nicely. Her mother wants to know whether she will need transfusions, since her blood pressure was so low before the surgery.Will she need transfusions to maintain her systemic volume?

No. Now that the shunt has been repaired, her blood is not being diverted from the systemic circuit into the pulmonary circuit, and her blood pressure should return to normal.

Which chamber receives blood from the superior and inferior vena cavae?

right atrium

Drag and drop the correct item name to complete each sentence.Terms may be used more than once or not at all.

1. The superior vena cava carries oxygen-poor venous blood from above the diaphragm from areas of the upper body and extremities into the right atrium. 2. The coronary sinus carries oxygen-poor venous blood of the coronary circulation into the right atrium. 3. The inferior vena cava carries oxygen-poor venous blood from below the diaphragm from the areas of the lower body and extremities into the right atrium.