Cytoplasm. The cytoplasm is the part of the cell which does all the work. Different cells do different jobs, however whatever the job is it will require energy in the form of a chemical called ATP. This energy containing chemical is produced by tiny organelles in the cell called mitochondria. Muscle cells contain two very special chemicals called actin and myosin.
Definition of TREPHINATION. : an act or instance of perforating the skull with a surgical instrument. ADVERTISEMENT.efinition of TREPHINATION. : an act or instance of perforating the skull with a surgical instrument. ADVERTISEMENT.
44 thoughts on â An illustrated history of trepanation â. What a completely fabulous post! I was planning to review the medical history of trepanation a few weeks ago, but was dragging my heels on the necessary research.ut after a time I realized a hole in the spine would heal over so it had to be in the skull, where holes stay open. Trepanation, or trephination (both derived from the Greek word trypanon, meaning âto boreâ) is perhaps the oldest form of neurosurgery.