Diffusion is the movement of particles from a high to low particle concentration, while osmosis is the movement of water from a high to a low water concentration.
Explanation:
Osmosis refers to the movement of water molecules through a selectively permeable membrane. The movement always occurs from the region of higher concentration of water to that of lower concentration. Osmosis does not include the movement of solutes.
Diffusion is the movement of substances from higher to lower concentration region. Diffusion is not restricted to movement of water only.
It is important that the daughter cells have a copy of every chromosome, so the process involves copying the chromosomes first and then carefully separating the copies to give each new cell a full set.