Which of the following facilitates opening of stomatal aperture?
| 1. | Decrease in turgidity of guard cells |
| 2. | Radial orientation of cellulose microfibrils in the cell wall of guard cells |
| 3. | Longitudinal orientation of cellulose microfibrils in the cell wall of guard cells |
| 4. | Contraction of outer wall of guard cells |
Opening and closing of stomata are due to the:
1. Hormonal change in guard cells
2. Change in Turgor pressure of guard cells
3. Gaseous exchange
4. Respiration