Cells are surrounded by semipermeable membranes too. Active transport through the membranes. The other way to transport ions and molecules through cell membranes is dialysis. Osmotic membranes and dialyzing membranes the difference is in the pore size. Osmotic membranes have smaller pores.
Osmosis is the net migration of water through an osmotic membrane.
A dilute solution, 0.200 M of sugar in water, is separated from pure water by osmotic membrane. The ions in ionic compounds individually affect osmotic pressure. Dialysis is analogous to osmosis but the pores in the membrane are larger It is affected by colloidal osmotic pressure. Dialysis and the bloodstream. Solutions with equal osmolarity are called isotonic.