A cell is like a busy city. For example, in the cell’s nucleus, the mayor is running city hall, while the cell membrane is the border. Mitochondria are the power plants. Just like a real town, there’s space between all the important structures. However, a cell does not have green grass surrounding its buildings. Cytosol is the fluid filler around the nucleus and organelles.
In eukaryotes, all the space inside the cell membrane but outside the nucleus is the gel-like cytoplasm. If a cell were a city, the cytoplasm would be everything inside the borders except town hall. The open areas -- lawns, gardens and parks -- are like the cytosol within a cell.This fluid contains water, salts, proteins and other organic particles. Cytosol is part of the cytoplasm but does not contain membranes, organelles or the nucleus.