The cytosol (cf. cytoplasm, which also includes the organelles) is the internal fluid of the cell, and a part of cell metabolism occurs here.
Proteins within the cytosol play an important role in signal transduction pathways and glycolysis.
Cytosol mostly consists of water, dissolved ions, small molecules, and large water-soluble molecules (such as protein). It contains about 20% to 30% protein.
Normal human cytosolic pH is (roughly) 7.0 (i.e. neutral), whereas the pH of the extracellular fluid is 7.4.
The texture of cytosol being described as granular can be attributed to the fact that in order to study the texture, an electron microsope must be used, which requires a process of dehydration prior to study.
Life: the science of biology. Purves, Sadava, Orians, Heller. Sunderland, MA. Sinauer Associates, Inc. 2004. (ILM USA)
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Intracellular fluid content in humans
The cytosol is a crowded solution of many different types of molecules that occupy up to 30% of the cytoplasmic volume.