A. X is true and Y is false.
B. X is false and Y is true.
C. X and Y are both true.
D. X and Y are both false.

_____1. X. Oxygen is taken up in the body during inhalation.
Y. Oxygen is delivered to the tissue by the respiratory system.
_____2. X. Oxygen gas comes from alveolus to capillary.
Y. Carbon dioxide comes from capillary to alveolus.
_____3. X. Blood that flows from the lungs is deoxygenated blood.
Y. Blood that flows from the body is oxygenated blood.
_____4. X. The aorta is the main and the biggest artery in the human body.
Y. It carries oxygenated blood away from the heart.
_____5. X. The heart is divided into four valves.
Y. The valves of the heart are the left and right atria and the left and right
ventricles.