Cytoplasm
The cytosol contains a complex mixture of cytoskeleton filaments, including the endoplasmic reticulum and the Golgi apparatus. It includes dissolved molecules, and water that fills much of the cell. Due to this network of fibres, membranes and the many dissolved macromolecules such as proteins, the cytosol does not act like a simple liquid. The main function of the cytoplasm is to hold the organelles in place.