pro·to·plasm (prō'tə-plăz'əm)
n.
The complex, semifluid, translucent substance that constitutes the living matter of plant and animal cells and manifests the essential life functions of a cell. Composed of proteins, fats, and other molecules suspended in water, it includes the nucleus and cytoplasm
protoplasm, term once used for the fundamental material of which all living things were thought to be composed. It was studied by a number of early scientists, especially by Félix Dujardin, J. E. Purkinje, M. J. S. Schultze, and Hugo von Mohl (who is credited with introducing the name), all working in the 19th cent. Many of the notions associated with the term have survived. Thus it is still accepted that all living organisms are made largely of the same classes of substances such as salts and organic molecules, that some of these are organized into structures large enough to be seen in the microscope and that water almost always is by far the most abundant material. However, the term is rarely used any more in a strictly scientific sense, although it survives in more literary usages. The unity of living matter is now most often described in terms of the cell as the unit of all living organisms (viruses, which are noncellular are at the border of life, being unable to reproduce independently outside living cells) and of the ubiquity of key biochemical molecules, especially nucleic acids and proteins.
protoplasm (proh-tuh-plaz-uhm)
The jellylike material in a cell, both inside and outside the nucleus, where the chemical reactions that support life take place.
protoplasm
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.
cy·to·plasm (sī'tə-plăz'əm)
n.
The protoplasm outside the nucleus of a cell.
Cytoplasm
The substance within a cell including the organelles and the fluid surrounding the nucleus.
cytoplasm
Portion of a eukaryotic cell outside the nucleus. The cytoplasm contains all the organelles (see eukaryote). The organelles include the mitochondria, chloroplasts, endoplasmic reticulum, Golgi apparatus, lysosomes, and peroxisomes. The cytoplasm also contains the cytoskeleton and the cytosol (the fluid mass that surrounds the various organelles).
cytoplasm (seye-tuh-plaz-uhm)
The material within a biological cell that is not contained in the nucleus or other organelles.
cytoplasm
Cytoplasm is a homogeneous, generally clear jelly-like material that fills cells. The cytoplasm consists of cytosol and the cellular organelles, except the cell nucleus. The cytosol is made up of water, salts, organic molecules and many enzymes that catalyze reactions. The cytoplasm plays an important role in a cell, serving as a "molecular soup" in which the organelles are suspended and held together by a fatty membrane. It is found within the plasma membrane of a cell and surrounds the nuclear envelope and the cytoplasmic organelles.
Components of the cytoplasm
The aqueous component of the cytoplasm (making up 80 percent of it) is composed of ions and soluble macromolecules like enzymes, carbohydrates, different salts and proteins, as well as a great proportion of RNA. The cytoplasm's watery component is also known as hyaloplasm.
The watery component can be more or less gel-like or liquid depending on the milieu's conditions and the activity phases of the cell. In the first case, it is named cytogel and is a viscid solid mass. In the second case, called cytosol, is a liquid in movement. In general, margin regions of the cell are gel-like, and the cell's interior is liquid.
The insoluble constituents of the cytoplasm are organelles (such as the mitochondria, the chloroplast, lysosomes, peroxysomes, ribosomes), several vacuoles, cytoskeletons, as well as complex membrane structures like the following:(e.g., endoplasmic reticulums and the Golgi apparatus).
Differences between animal and plant cytoplasm
While all cells possess a cytoplasm, cells from different biological domains can differ widely in the characteristics of their cytoplasms. In the animal kingdom, cytoplasm occupies nearly half the cell's volume, while in plant cells, the cytoplasm occupies much less space because of the presences of vacuoles.
Function
The cytoplasm plays a mechanical role, that is, to maintain the shape and consistency of the cell, and to provide suspension to the organelles. It is also a storage place for chemical substances indispensable to life, which are involved in vital metabolic reactions, such as anaerobic glycolysis and protein synthesis.
Cytoplasm in popular culture
In the Magic: The Gathering set of Ravnica, Cytoplasm is a translucent jelly-like creature. Cytoplasm was developed by the Simic Combine under their edict of designing an ecosystem that can survive a completely urbanized plane, with the added benefit of not requiring the need to processes that would require consent. Once bonded to a living creature, cytoplasm leeches the DNA of the creature, improving its strength and survivability. If that cytoplasm is than grafted onto another creature, it gains salient properties from the original host.
For example, if a human has cytoplasm from a troll (known for their regenerative properties) grafted onto him (most cytoplasm-improved creatures develop ways of transferring cytoplasm without requiring informed consent, the human now shares the regenerative abilities.
Cytoplasm composes the entirety of the Simic project Experiment Kraj, a cytoplastic entity that can choose its own evolution by taking the properties of any being with cytoplastic enhancements
2006-08-04 05:21:47
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answer #4
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answered by Monica 3
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