The loss of water through cuticle may reach upto :

1. 5%

2. 10%

3. 20%

4. 40%

Which ion accumulate in the guard cells at the time of opening of stomata :

1. P

2. K

3. Mg

4. Ca

Bulliform cells respond to which change?

1. Turgor pressure

2. Osmotic pressure

3. Photosensitive

4. None of above.

Passive absorption of minerals depends on :

1. Temperature

2. Temperature and metabolic inhibitor

3. Metabolic inhibitor

4. Humidity

Dry wooden stakes if driven into a small crack in a rock and then soacked, can develop enough pressure to split the rock. Such a pressure is built up through the phenomenon of :

1. Imbition

2. Butteress roots

3. Prop roots

4. Turgor pressure

The cohesive force existing between molecules of water is contributing to :

1. ascent of sap

2. translocation

3. plasmolysis

4. osmosis.

To initiate cell plasmolysis, the salt concentration must be :

1. isotonic

2. hypertonic

3. hypotonic

4. atonic

The most accepted theory for stomatal opening and closing is :

1. transpiration

2. guard cell photosynthesis

3. K⁺ efflux and influx

4. starch glucose interconversion.

Ascent of sap is mainly attributed to :

1. cohesion force

2. imbibition

3. root pressure

4. capillarity

Water lost by transpiration is :

1. rich in solutes

2. rich in dissolved roots

3. rich in dissolved minerals

4. pure water.