The question is actually difficult because an organism can be an microorganism or an animal with organs, so it's impossible to say which ones bigger.
Only if you allow for comparisons between life forms. If you assume that he's speaking of a single life form that contains all the systems then the question is well-defined.
Only if you allow for comparisons between life forms. If you assume that he's speaking of a single life form that contains all the systems then the question is well-defined.