The Cardiovascular System Practice Questions

1. c. The four-chambered vertebrate heart is made up of the right and left ventricles and the right and left atria. The atria receive blood from the body (the vena cava) and the lungs (the pulmonary vein). The ventricles push blood out of the heart to the body (the aorta) or the lungs (the pulmonary artery).

2. a. Remember that all veins carry blood toward the heart and all arteries carry blood away from the heart. Thus, usually arteries (like the aorta) will be carrying oxygenated blood, and veins (like the vena cava) will be carrying blood that is not oxygenated. However, in the heart-to-lung part of the system, the vessel carrying blood away from the heart and toward the lungs is an artery (the pulmonary artery), but it is carrying blood that is not oxygenated because that's why it's going to the lung (to become oxygenated). Likewise, the vessel carrying blood from the lungs to the heart (the pulmonary vein) is carrying blood that has been oxygenated.

3. b. Blood is a suspension of the fluid we call plasma and the cells that are suspended throughout it. The cells are the red and white blood cells and the platelets.

4. a. Platelets aid in the clotting of blood to seal off a wound and prevent blood loss or infection.

5. c. Capillary beds are between the very small arteries called arterioles and the very small veins called venules. Capillary beds are the site of gas exchange in the circulatory system.

6. b. Red blood cells carry oxygen, but they also carry carbon dioxide.