i think its the veins or it might be the arteries
Both veins and the pulmonary arteries contain oxygen poor blood that also has greater amounts of carbon dioxide.
Ok, this is what you do to find that out: look in a Biology textbook because I don't know. Check back later for a real answer.
The pulmonary artery
left ventricle
Venous blood is loaded with carbon dioxide and low in oxygen Arterial blood is rich in oxygen with little carbon dioxide
Chemoreceptors detect the levels of carbon dioxide in the blood.
Red blood cells take carbon dioxide (CO2) away from body tissues. The carbon dioxide is then transported to the lungs where it can be exhaled.
blood pH
Depending on the levels of hydrogen ions, carbon dioxide is converted into bicarbonate in the blood
Lowest carbon dioxide content would be the vessel right after the lungs, pulmonary vein to the left atrium.
The blood entering from the lungs has a high oxygen content and the blood entering from the body is high in carbon dioxide.
Venous blood is loaded with carbon dioxide and low in oxygen Arterial blood is rich in oxygen with little carbon dioxide
Oxygenated blood is red. The presence of carbon dioxide in the blood does not alter the color.
Chemoreceptors detect the levels of carbon dioxide in the blood.
Carbon dioxide and water
Deoxygenated blood is low in oxygen and high in carbon dioxide.
The right side of the heart takes the blood returning from the body and sends it to the lungs. It is high in carbon dioxide and low in oxygen. After the blood goes to the lungs it returns tot he left side of the heart to be pumped back out tot he body and it low in carbon dioxide and high in oxygen.
The lung takes carbon dioxide out of your blood and replaces it with oxygen.
aorta
The mechanisms for transporting oxygen and carbon dioxide in the blood are the lungs. The blood vessels are also needed for transporting oxygen and dispelling carbon dioxide.
Red blood cells take carbon dioxide (CO2) away from body tissues. The carbon dioxide is then transported to the lungs where it can be exhaled.