Cytoplasm

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Organelles. Cytoplasm labeled at center right.

Schematic of typical animal cell, showing subcellular components. Organelles: (1) nucleolus (2) nucleus (3) ribosome (4) vesicle (5) rough endoplasmic reticulum (ER) (6) Golgi apparatus (7) Cytoskeleton (8) smooth ER (9) mitochondria (10) vacuole (11) cytoplasm (12) lysosome (13) centrioles

Cytoplasm is a 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 nucleus and envelopes the organelles.

[edit] Function

The cytoplasm holds all of the cellular organelles outside of the nucleus and also maintains the shape and consistency of the cell. 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.

[edit] Components of the cytoplasm

The cytoplasm 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.

It 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 viscous solid mass. In the second case, called cytosol, it acts like a liquid. In general, margin regions of the cell are gel-like, and the cell's interior is liquid.

The organelles (such as the mitochondria, the chloroplast, lysosomes, peroxysomes, ribosomes, vacuoles, cytoskeletons, and complex cell membrane structures like the endoplasmic reticulums)in the cytoplasm are insoluble.

[edit] Differences between the animal and plant cytoplasms

While all cells possess 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 presence of vacuoles.