With my knowledge, I can easily posit the difference between these four scientific phenomenons. Osmosis, beyond a reasonable doubt, is the movement of water from a region of hypotonic solution (lower concentration) to a region of hypotonic solution (higher concentration). Diffusion is the movement of molecular particles or ion from a region of higher concentration to a region of lower concentration; It may occur or otherwise through a permeable membrane.
Active transports, on the one hand, are protein molecules function as molecular pumps to the cell to accumulate ions against a concentration gradient. On the other hand, passive transport or facilitated transport allows ions or molecules to cross to the semi-permeable membrane because of the Permeates present in the membrane, which eventually ensures effective transport. Just like the simple diffusion, passive transport does not need metabolic energy, but instead, they simply occur across the concentration gradient.
Osmosis is a process by which molecules of a solvent pass through a semipermeable membrane from a less concentrated solution into a more concentrated one, thus balancing the concentrations on each side of the membrane. Diffusion is the net movement of molecules or atoms from an area of high concentration, which is high chemical potential to a state of low concentration, which is low chemical potential.
This state is also referred to as the movement of a substance down a concentration gradient. Active transport is the progression of ions or molecules across a cell membrane into a region of a higher concentration, assisted by enzymes and requiring energy. Passive transport is the transport of biochemicals and other atomic or molecular substances across cell membranes without the need for energy input.