Protoplasm
From Free net encyclopedia
Protoplasm is the living substance inside the cell. At the simplest level, it is divisible into cytoplasm and nucleoplasm. It is also sometimes termed "bioplasm", (Beale: meaning the essential substance of living matter within a cell) and is distinct from non-living cell components lumped under "ergastic substances". Ergastic substances can occur in the protoplasm. In many plant cells most of the volume of the cell is not occupied by protoplasm, but by "tonoplast": a large water filled vacuole enclosed by a membrane.
The idea that protoplasm is 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 powerful microscope of organic and inorganic substances, mysteriously directed by the nucleus and controlled by the cell membrane. Today, it is known that the cytoplasm is structurally very complex, and that protoplasm is living because of the complexity of the "cytoplasmic organeles" and their careful separation and orchestration of multiple chemical processes.
Charles Darwin and his contemporaries viewed "protoplasm" as the sole content of a cell, in other words, cells were nothing but simple blobs composed of protoplasm. This simplified view of "cells biology" circumvented the problem of the origin of life that Darwin and others struggled with. However, that problem was later introduced in the 1950s when the complex structure of DNA was discovered.
The concept of protoplasm is the essence of life, being something nearly sacred, induplicable by man. Organisms are able to ingest chemicals produced by nature and made in a laboratory. It can evolve into quite a number of other living creatures.
Protoplasm exists in three forms: solid state, liquid state and sometimes a combined solid and liquid state.
Whether the protoplasm is in either of the three forms depends upon the physiological state of the cell.da:Protoplasma de:Protoplasma es:Protoplasma eo:Protoplasmo it:Protoplasma mk:Протоплазма nl:Protoplasma ja:原形質 pl:Protoplazma simple:Protoplasm sv:Protoplasma