Question

how is oxygen transported in large multi cellular organisms like humans​

Answer 1

Answer:

Haemoglobin transports oxygen molecule to all the body cells for cellular respiration .The haemoglobin pigment present in the blood gets attached to O2 molecules that are obtained from breathing and thus forms oxyhaemoglobin .This oxygenated blood is then distributed to all the body cells by the heart. After giving away O2 to the body cells, blood takes away CO2 which is the end product of cellular respiration and blood becomes deoxygenated.

Explanation:

Answer 2

Respiration ensures that cells, tissues, and major organs of the body receive an adequate supply of oxygen and that the carbon dioxide, a waste product, is efficiently removed; the exchange of oxygen and carbon dioxide occurs via diffusion across cell membranes.