carbon, hydrogen, nitrogen and oxygen.

where do organisms get those elements?

Well, where do you think they get them from? This is a homework section, so we're not going to just give you the answers. You need to tell us where you're at in terms of the question and what you're stuck on, specifically.

The question can't be answered anyway without more information, autotrophs and heterotrophs gain these from vastly different sources.

difficult to answer actually it can't be answered in the first place

difficult to answer actually it can't be answered in the first place

 

 

Is that a fact? I suggest you open another thead and we'll discuss the idea "it can't be answered"....

Edited October 31, 201114 yr by Moontanman