Answer:
Been brought about by the cell theory announced by Theodor Schwann and Matthias Schleiden in 1838, whereby cells were held to be the basic units of all living tissues. Improvements in the microscope during the 19th century made it possible gradually to lay bare the basic structures of cells.
Explanation:
Answer:
cellular respiration...that's breathing out of humans
and through human activities like burning of fossil fuels...
Answer: Prokaryotic cells have free flowing DNA. This DNA is in a circular shape and flows freely in the cytoplasm
I believe that would be an open system.