who or what 
btw this is 6th grade science and this is not a true or false question
                                             
                                          
                                          
                                        
											 
											answer:
this is the cell theory, which was proposed by Theodor Schwann in 1839
explanation:
Answer:
This is called cell theory. This was first proposed by Theodor Schwann and became an important part of science today.