Plant Water Relationships

Exudation of xylem sap on cutting the shoot is due to

• Transpiration

• Guttation

• Root Pressure

• None of the above

Plasmolysis occurs due to

• Absorption

• Cavitation

• Endosmosis

• Exosmosis

Water exudation through hydathodes is

• Guttation

• Bleeding

• Transpiration

• Exosmosis

A cell immersed in a solution increases in volume. The solution is

• Hypertonic

• Isotonic

• Hypotonic

• Either a or b

Out of 1M solution of sucrose and 1M solution of NaCl, water potential of

• Sucrose solution will be greater

• NaCl solution will be greater

• Both will have equal

• Independent of Concentration of solution

Root hair cells under ordinary conditions typically have a water potential in the range

• 1 to 4 bars

• -1 to 4 bars

• 1 to 2 bars

• -1 to -2 bars

Root Pressure is maximum when

• Transpiration is high and Absorption is very low

• Transpiration is very low and Absorption is very high

• Absorption and transpiration both are high

• Absorption and transpiration both are low

Stomata opening during the day and close at night because

• Photosynthesis occurs during the day time only

• Enzymes convert starch into sugar at elevated pH in light

• Loss of sugars increase osmotic concentration of the cell sap

• Loss of starch in day time raises OP of subsidiary cells

Maximum transpirational pull will be observed under conditions

• Open stomata, high humidity, well irrigated soil

• Open stomata, low humidity, well irrigated soil

• Open stomata, high humidity, dry soil

• Closed stomata, low light intensity, high humidity

During stomatal closure K+ ions

• Join with chloride ions

• Join with malate ions

• Transported out to subsidiary cells

• Accumulated in the vacuole of guard cells