Question

The main carrier of oxygen and carbon dioxide in humans

Answer 1

in humans blood cannot be transported to all the parts of the body by diffusion alone so a pigment is used to transport it

in humans this pigment is caleed haemoglobin..........

so the main carrier of oxygen is haemoglobin but the carrier of carbondioxide is blood because carbondioxide gets dissolved in blood

Answer 2

haemoglobin forms a complex with oxygen known as oxyhaemoglobin due to its high affinity for oxygen.hence transported by blood.

whereas, co2 is highly soluble in water. hence carried by plasma of blood made of 90% water.
hope it works.