How is oxygen and carbon dioxide transported in human beings ?

Explanation

Main exchange of gases takes place between the alveoli of lungs and the surrounding blood capillaries.
Transport of Oxygen: Haemoglobin transports oxygen molecule to all the body cells for cellular respiration. The haemoglobin pigment present in the blood gets attached to `O_(2)` molecules and forms oxyhemoglobin. This oxygenated blood is then distributed to all the body cells by the heart. Oxygen is absorbed by the blood capillaries from the lungs alveoli by diffusion After giving away `O_(2)` to the body cells, blood takes away `CO_(2)` which is the end product of cellular respiration and blood becomes de-oxygenated.
Transport of carbon dioxide: Since haemogłobin pigment has less affinity for `CO_(2)`, it is mainly transported in the dissolved form. This deoxygenated blood gives `CO_(2)` to lung alveoli in exchange and where it moves out of the body through exhalation.