Turgor pressure in mesophyll cells ⇒ help to support the leaf and keep it firm.
enables it to spread out widely ⇒ to absorb light for photosynthesis
In strong, hot and dry weather ⇒ when ROT excess Rate of absorption of water by roots ⇒ cells lose their turgor
They become flaccid ⇒ plant wilts
Wilting also occurs in soft stems of some plants ⇒ Balsam
Cells of stem lose water
Advantages of Wilting
- When leaf folds up due to wilting ⇒ SA that is exposed to light is reduced.
- Reduces exposed SA of leaf ⇒ reduce exposure of stomata to atmosphere ⇒ as guard cells → become flaccid and reduce significantly in size ⇒ reduces Rate of water loss through stomata.
- Excessive loss of water ⇒ causes guard cells ⇒ to become flaccid and stomata to close.
- rate of transpiration is reduced
Disadvantages of Wilting Stomata are closed ⇒ amount of entering leaf through diffusion is also reduced > becomes limiting factor > and rate of photosynthesis is decreased. Folding of leaf ⇒ can also reduce exposed SA to Light. Also reduces rate of photosynthesis.
Calculating Rate of transpiration Rate of transpiration (g/h) =