Question: what is the fluid substance of cell known as
Answer: The idea that protoplasm of eukaryotes is simply divisible into a ground substance called `` cytoplasm '' and a structural body called the cell nucleus reflects the more primitive knowledge of cell structure that preceded the development of electron microscopy , when it seemed that cytoplasm was a homogeneous fluid and the existence of most sub-cellular compartments , or how cells maintain their shape , was unknown .