Water potential in the leaf tissue is positive (+ve) during:
1. Excessive transpiration
2. Low absorption
3. Low transpiration
4. High Transpiration
If cohesion-tension transpiration theory is correct then a break in water column in xylem vessels :
1. should cause the mesophyll cells to become flaccid and result in wilting of leaves.
2. should increase the water contents of leaves
3. shouls have no effect at all
4. should increase the rate of photosynthesis.
Which one is not related to transpiration?
2. Circulation of water
3. Absorption and distribution of mineral salts
4. Regulation of plant body temperature.
A plasmolysed cell can be deplasmolysed by placing it in :
1. Pure water or hypotonic solution
2. Hypertonic solution
3. Isotonic solution
4, Saturated solution
If alcohol treated cell is kept in hypertonic solution it:
3. Remains same
The loss of water through cuticle may reach upto :
Dry wooden stakes, if driven into a small crack in a rock and then soaked, can develop enough pressure to split the rock. Such a pressure is built up through the phenomenon of :
2. Buttress roots
3. Prop roots
4. Turgor pressure
The cohesive force existing between molecules of water is contributing to :
1. ascent of sap
To initiate cell plasmolysis, the salt concentration must be :
Ascent of sap is mainly attributed to :
1. cohesion force
3. root pressure