What is the Symbiotic Theory?

Its an evolutionary theory that explains the origin of eukaryotic and prokaryotic cells.

The symbiotic theory is a theory of the origin of eukaryotic organelles. It is referred as symbiogenesis. It is an evolutionary theory that explains how eukaryotic cell came from prokaryotes. It states that several key organelles of eukaryotes originated as a symbiosis between separate single-celled organisms. Hope this answers the question.