Question

Why do plants not need an oxygen carrier like the humans in whom oxygen is carried by heanmoglobin

Answer 1

There is no need of of an oxygen carrier in plants because plantssynthesise oxygen during photosynthesis and they consumeoxygen during respiration. All parts ofplants perform respiration and getsoxygen directly. So, they do not needan additional carrier to transport oxygen

Answer 2

when the body  size increases the diffusion pressure alone cannot take care of oxygen delivery to all parts of the body.

plants do not require oxygen carriers as they are not huge.

btw they release oxygen so I don't specifically they need oxygen carriers.

                              hope this helps!!!!!!