The main cause of guttation in plants is root pressure. During night when root pressure is high, water drops ooze out with the assistance of special structures called hydathodes which help in guttation.

Correct Option: D

The main cause of guttation in plants is root pressure. During night when root pressure is high, water drops ooze out with the assistance of special structures called hydathodes which help in guttation.

Rupture and fractionation do not usually occur in the water column in vessel/ tracheids during the ascent of sap because of cohesion and tension. The water molecules have a great mutual attraction to each other or tremendous cohesive power which is sometimes as much as 350 atmospheres. Thus, the transpiration pull develops a negative pressure in the uppermost xylem cells. It is transmitted from there into the xylem of stems, and then to the roots.

Correct Option: B

Rupture and fractionation do not usually occur in the water column in vessel/ tracheids during the ascent of sap because of cohesion and tension. The water molecules have a great mutual attraction to each other or tremendous cohesive power which is sometimes as much as 350 atmospheres. Thus, the transpiration pull develops a negative pressure in the uppermost xylem cells. It is transmitted from there into the xylem of stems, and then to the roots.

Bending of tentacles in Venus fly trap or Drosera after coming in contact with an insect is thigmonastic or chemonastic movement of variation or turgor movement. The mechanism by which the trap snaps shut involves a complex interaction between elasticity, turgor and growth. In the open, untripped state, the lobes are convex, but in the closed state, the lobes are concave It is the rapid flipping of this bistable state that closes the trap, but the mechanism by which this occurs is still poorly understood. When the trigger hairs are stimulated, an action potential involving calcium ions is generated, which propagates across the lobes and stimulates cells in the lobes and in the midrib between them.

Correct Option: D

Bending of tentacles in Venus fly trap or Drosera after coming in contact with an insect is thigmonastic or chemonastic movement of variation or turgor movement. The mechanism by which the trap snaps shut involves a complex interaction between elasticity, turgor and growth. In the open, untripped state, the lobes are convex, but in the closed state, the lobes are concave It is the rapid flipping of this bistable state that closes the trap, but the mechanism by which this occurs is still poorly understood. When the trigger hairs are stimulated, an action potential involving calcium ions is generated, which propagates across the lobes and stimulates cells in the lobes and in the midrib between them.

After rain a portion of water percolates downward under the influence of gravity. It is not available to plants. Hygroscopic water is also not available for plants because soil particles hold water by strong attractive forces. Chemically bound water is water combined with chemicals. Capillary water is present in narrow spaces of soil and is held in soil by capillary forces and is absorbed by root. 26. (c) Pitcher plant is an insectivorous plant which catches insects. The paratonic movements are induced in response to an external stimulus caused by insects due to which lids close and the insects are trapped inside the pitcher.

Correct Option: B

After rain a portion of water percolates downward under the influence of gravity. It is not available to plants. Hygroscopic water is also not available for plants because soil particles hold water by strong attractive forces. Chemically bound water is water combined with chemicals. Capillary water is present in narrow spaces of soil and is held in soil by capillary forces and is absorbed by root. 26. (c) Pitcher plant is an insectivorous plant which catches insects. The paratonic movements are induced in response to an external stimulus caused by insects due to which lids close and the insects are trapped inside the pitcher.

Water is absorbed by a system having higher DPD from another system with lower DPD. The net force with which water is drawn into a cell is equal to the difference of osmotic pressure (OP) and turgor pressure known as diffusion pressure deficit (DPD).
DPD = OP – TP

Correct Option: C

Water is absorbed by a system having higher DPD from another system with lower DPD. The net force with which water is drawn into a cell is equal to the difference of osmotic pressure (OP) and turgor pressure known as diffusion pressure deficit (DPD).
DPD = OP – TP