It is the roots or the leaves?

[red devil]

Which part of an aquarium plant absorbs the co2, the roots or the leaves/stem?

[Ozymandias]

i think the whole plant to be honest

[DominionDesign]

My understanding is CO2 is primarily through the leaves while ferts are adsorbed by the whole plant.

[Mgamer20o0]

Leaves

http://www.caribbeanedu.com/images/kewl/photosynthesis.gif

[khombre]

leafs

Uhmm.. that's "Leaves" MG lol hehe :)

Same goes for aquatics and non-aquatics?

[paperdragon]

Same goes for aquatics and non-aquatics?

Yup. The vast majority of plants, whether aquatic or not, have the same basic process.

[Spewn]

Leaves for CO2, roots for oxygen.