Evidence is not wanting, however, that the cytoplasm must be regarded as, fundamentally, a semifluid, homogeneous substance in which by its own activity, granules, vacuoles, fibrils, &c., can be formed as secondary structures.
The protoplasm of a living cell con.sists of a semifluid granular substance, called the cytoplasm, one or more nuclei, and sometimes centrosomes and plastids.