| Osmotic Pressure | Osmotic Potential |
| 1.Osmotic pressure is the minimum pressure which needs to be applied to a solution to prevent the inward flow of water across a semipermeable membrane. | 1.Osmotic potential is defined as the ability of a solution to draw water in when separated from another solution by a semi-permeable |
| 2. It is expressed in bars with a positive sign. | 2. It is expressed in bars with a negative sign. |
What cause the opening and closing of guard cells of stomata during transpiration ?
Explain why xylem transport is unidirectional and phloem transport bi-directional.
