Comparison Basis

Diffusion

Osmosis

Facilitated Transport

Active Transport

Definition

This is the Process of passive movement of Molecules or particles from the region of higher concentration to the region of lower concentration until an equilibrium concentration is maintained between two regions. This is a Passive process

This is a special type of diffusion process where the solvent molecules move from region of low concentration to the region of high concentration through the semi permeable membrane. This is a passive process.

This is a process where the movement of molecules from the region of higher concentration to the region of lower concentration (down the concentration gradient) with the help of a carrier protein. It is a passive process.

This is the process of movement of molecules against the concentration gradient.  Here the movement of molecules occurs from the region of lower concentration to the region of higher concentration. It is an Active Process.

Examples

 Exchange of oxygen between the air and the blood stream, Exchange of Carbon dioxide between the air and leaf

Plant roots absorb water by this process. Colon, stomach and small intestine also absorb water by this process.

Movement of Glucose, sodium ions and potassium ions in and out of the cells.

In the excretion process Reabsorption of some of the useful compounds like glucose, salts and amino acids occurs by this process.

Occurrence

This process takes place in any medium whether it is solid medium, liquid or gas.

This is the process which takes place only in the liquid medium.

This process occurs across the cells.

This process occurs across the cells.

Semi Permeable Membrane

This Process does not require the semi permeable membrane.

This process requires the semi permeable membrane.

This process requires the semi permeable membrane.

This process requires the semi permeable membrane.

Energy Requirement

Energy is not required

Energy is not required

Energy is not required

Energy is required and this energy is obtained from the ATP which is generated  by respiration process.

Requirement of Carriers

Carriers are not required.

Carriers are not required.

Carriers are required and the carrier will have specific size and shape.

Some of the special proteins present in the cell membrane acts special carriers for this process.

Process Rate

This is a Fast process

This is a Slow Process

Occurs fast when the solute concentrations are less and slow when the solute concentrations are high.

Fast process as the energy is involved.

Process Significance

This is an  important process in animals especially during the process of creating energy as it helps in the exchange of gases in the process of respiration also it helps plants in the exchange of carbon dioxide from the ir to carry out the process of Photosynthesis.

This process is important for plants to absorb water from the plant roots and also to absorb water from alimentary canal this process is required.

This process is important for the diffusion of Glucose across the cells.

Occurrence of this transport process is important as it will allow the cell for the movement of molecules or substances against the concentration gradient.