Each living cell contain protoplasm, which in simple terms is cytoplasm and the cellular nucleus. It is made up of water, electrolytes, proteins, inorganic salts, glucose, lipids (fat substances), among other elements.
Now let’s look at the structure of the eukaryotic cells of animals, specifically those of our body.
The cytoplasm, which comprises the total volume of the cell (except for the nucleus), is the means by which the chemical alterations and metabolic reactions occur in a cell. It is made up of a viscous, watery solution (called cytosol) that includes numerous specialized structures and cellular organelle.
The most notable organelle is the nucleus, which measures between 5 and 10 microns (a micron is one millionth of a meter) and is surrounded by a double membrane. The inside communicates with the cytoplasm by way of openings in the walls of the membrane (nuclear pore). On the inside of the nucleus you can find the nucleolus, which is a structure that intervenes in the formation of the ribosomal subunits.