Cytoplasm

As the cytoplasm or cytoplasm ( from Ancient Greek κύτος kytos " vessel ", " cavity " and πλάσμα plasma " formations " ) is the cell called filling basic structure of the liquid cytosol (matrix cytoplasmatica ) with different solutes and the firmer cytoskeleton ( cytoskeleton ) exists. It is bounded to the outside of the cell membrane ( membrane cellularis, Cytolemma or plasmalemma in plant cells). In their organelles ( organ Ella ), including the nucleus (nucleus ) contained and defined by several membranes to the cytoplasm ( This view is controversial, and some consider the organelles as part of the cytoplasm ). The word " cytoplasm " of the German anatomy professor Albert Kölliker of 1863 was introduced as a synonym for " protoplasm ". It was not until 1882, the cytoplasm was called without nucleus and cytoplasm with plastids at the suggestion of Eduard Strasburger.

Terms

The cytoplasm is the basic substance of the cell. The entire ground substance, together with the cell organelles is called the cytoplasm. If the cell organelles were removed by centrifugation, referred to the product as cytosol. During the cytoplasm to the cell edges is more viscous and is called ectoplasm, it is inside a liquid and is called endoplasm.

Function

Within the cytoplasm from running many different chemical metabolic processes of the cell are controlled by enzymes. Here, each cell energy for all processes must be provided. In addition, cell-specific tasks, such as the formation of additional cell components in the growth, and reduction of undesirable build-up of substances to be stored or to be delivered as well as the transport of molecules through the membranes and through the cell.

Biomembranes are in the cytoplasm to enclose additional, different shaped rooms and to be defined separately. Such membrane-bound spaces within the cytoplasm called compartments or organelles, as they meet equally as " organs of the cell " certain functions in cell metabolism. By thus created different reaction chambers also opposing metabolic processes such as carbohydrate degradation can occur simultaneously alongside oxidation- reduction processes within the cytoplasm in addition to carbohydrate structure or.

The consistency of the cytoplasm can change between gel and sol, whereby a movement of all the particles included in the cytoplasm is also possible. This consistency arises because most of the water is bound in the hydration shells.

Chemical composition of the cytoplasm

In chemical respect is the cytoplasm of numerous organic, but also from inorganic materials. With 80 to 85 percent water content, the water content is high. The following list indicates the average composition in animal cells:

• Water from 80.5 to 85 %
• Proteins 10-15 %
• Lipids 2-4%
• Polysaccharides 0.1-1.5 %
• DNA 0.4 %
• RNA 0.7 %
• Small organic molecules 0.4%
• Inorganic molecules and ions of 1.5%

The pH of the cytoplasm is usually about seven. However, since often bound protons in metabolic reactions or be free, the cytoplasm is buffered. Can be changed or stabilized, the pH also by ion pumps.

In the cytoplasm is the cytoskeleton, which is dynamically assembled and disassembled. This stabilizes the cell, provides solid tracks for vesicle transport and causes intracellular movements such as the Zytoplasmaströmung, organelle transport and chromosome. The Zytoplasmaströmung takes place only in the endoplasm, it contributes to the mixing at.