How is oxygen and carbon dioxide transported in human beings?
In human beings, oxygen is transported by the respiratory pigment haemoglobin. Since diffusion pressure alone cannot take care of oxygen delivery to all parts of the large body, haemoglobin takes up oxygen from the air in the lungs. This pigment has a very high affinity for oxygen and is present in the red blood corpuscles. It carries the oxygen to tissues that are deficient in oxygen before releasing it.
Carbon dioxide is transported differently because it is more soluble in water than oxygen. Due to this property, carbon dioxide is mostly transported in the dissolved form in our blood.
Explanation
The answer is derived directly from the provided context which explains that haemoglobin (found in red blood corpuscles) is necessary for oxygen transport because diffusion is too slow for large bodies. It also highlights the specific mechanism for carbon dioxide transport based on its solubility in water.