How many of the following are true?
Almost all the oxygen (over 98%) that blood transports combines with the protein hemoglobin in red blood cells.
One red blood cell can carry a maximum of 4 oxygen molecules.
Oxygen attaches specifically to the iron atoms found in hemoglobin.
Approximately 2% of the oxygen in the blood is carried by the leukocytes.
The majority of carbon dioxide in the blood is carried by erythrocytes.
The most important carbon dioxide transport mechanism involves the formation of bicarbonate ions.