Are both of osmosis and diffusion movement of high concentration to low concentration? just a deferences of water or molecures?

Answer 1

Both are passive movements, i.e. no energy (ATP) is required.

Diffusion is basically a random movement of solute and water molecules in all directions. In a concentration gradient, area of higher concentration will contain more solute than that of low concentration. The net result of random movements is movement from high to low concentration until it is uniform (i.e. no more gradient) at which time movements are equal in both directions.

Osmosis is very much a restricted diffusion. In osmosis, there is always a semi-permeable membrane which restricts passage of some larger particles, such as solute bound to water. Generally, bigger molecules do not pass through the membrane, but water does. In time, more water pass from the low concentration to the higher concentration than the reverse. Note that lower concentration of solute means there are more molecules of solvent. This continues until the concentrations are equal on each side of the membrane.