Are the concentration of substances in the cell and the environment approximately the same?

The concentration of substances in the cell and in the environment is different. Many cellular elements are concentrated in a cell. Also, cell sap has a much higher density than water. The only thing that can be approximately the same both in the cell and in the environment is the amount of salt. This can be seen on the example of erythrocytes. If erythrocytes are placed in a saline solution with a large amount of salt (0.8% solution inside the erythrocyte), then the cell will “swell”, since by means of diffusion the amount of salt will be equalized with the environment.