Question

why the water molecules during osmosis move from both directions and why not in diffusion which takes place between the cell and the atmosphere

Answer 1

Dear student,

Diffusion could be defined as an exergonic process(does not require energy) in which there is spontaneous movement of particles from a high concentration area to a low concentration area.
Osmosis, is defined as ​a diffusion process in which there is movement of water across a semi-permeable membrane from ​dilute solution(solution with lower concentration of solute) to concentrated solution (solution with higher concentration of solute).
Osmosis could be of two types: Failitated diffusion- which does not require energy.
Active transport- which requires energy.

Regards.