What cells are affected in glomerulonephritis and how is there a disruption of diffusion or osmosis?

Red blood cells, and other cells of the circulatory system

Also the kidney cells in the kidney.

Diffusion occurs because of the movement of molecules from the region of higher concentration to the region of lower concentration. This movement of molecules occurs due to a thermal motion. Diffusion normally occurs between two compartments having difference in concentration. In case of fluid it moves from the region of higher concentration to the region of concentration until a balance is reached. The process of diffusion is very important for the humans as well. The oxygen that humans breathe in gets diffused with the blood.