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Protoplasm (/ ˈ p r oʊ t ə ˌ p l æ z əm /; [1] [2] pl. protoplasms) [3] is the part of a cell that is surrounded by a plasma membrane.It is a mixture of small molecules such as ions, monosaccharides, amino acids, and macromolecules such as proteins, polysaccharides, lipids, etc.
In 1839, he coined the term "protoplasma" for the fluid substance of a cell. He was one of the best known scientists of his time. He was one of the best known scientists of his time. Such was his fame that when people from outside Europe wrote letters to him, all that they needed to put as the address was "Purkyně, Europe".
Protoplast (from Ancient Greek πρωτόπλαστος (prōtóplastos) 'first-formed'), is a biological term coined by Hanstein in 1880 to refer to the entire cell, excluding the cell wall. [1] [2] Protoplasts can be generated by stripping the cell wall from plant, [3] bacterial, [4] [5] or fungal cells [5] [6] by mechanical, chemical or ...
Such criticisms stimulated continued studies on protoplasm as the principal agent determining cell permeability properties. In 1938, Fischer and Suer proposed that water in the protoplasm is not free but in a chemically combined form, and that the protoplasm represents a combination of protein, salt and water.
The term was introduced by Rudolf von Kölliker in 1863, originally as a synonym for protoplasm, but later it has come to mean the cell substance and organelles outside the nucleus. [ 4 ] [ 5 ] There has been certain disagreement on the definition of cytoplasm, as some authors prefer to exclude from it some organelles, especially the vacuoles ...
He coined the term cell (from Latin cellula, meaning "small room" [41]) in his book Micrographia (1665). [ 42 ] [ 40 ] 1839: Theodor Schwann [ 43 ] and Matthias Jakob Schleiden elucidated the principle that plants and animals are made of cells, concluding that cells are a common unit of structure and development, and thus founding the cell theory.
A decade after Aileen Lee coined the term “unicorn,” she knows that the term has taken on a life of its own—and is imperfect. “It’s an ephemeral word, it’s a point in time,” she told me.
The term osmosis originated in 1827 and its importance to physiological phenomena realized, but it wasn’t until 1877, when the botanist Pfeffer proposed the membrane theory of cell physiology. In this view, the cell was seen to be enclosed by a thin surface, the plasma membrane , and cell water and solutes such as a potassium ion existed in a ...