Which statement is correct?
1. Oxygen diffuses from large blood vessels into the body's cells.
2. In the blood, oxygen is bound to hemoglobin, a protein found in red blood cells.
3.Oxygen is released from the mitochondria as a product of cellular respiration.
4.Carbon dioxide diffuses from the alveoli into surrounding capillaries.
5.As oxygen diffuses from the lungs into capillaries, blood becomes deoxygenated.