Prepare for NEET with Botany-specific practice questions. Covering all major Botany chapters, this is perfect for your NEET Biology needs.
Under conditions of high transpiration pull, the primary driving force for water movement through the xylem is:
Root pressure generated by active transport of ions.
Capillary action within the narrow xylem vessels.
Active transport of water molecules by xylem parenchyma cells.
Cohesion and adhesion of water molecules, creating a continuous water column.
The cohesion-tension theory explains the ascent of sap in tall trees. Which of the following factors LEAST contributes to the maintenance of the continuous water column?
Active transport of water into xylem vessels
Cohesion between water molecules
Adhesion of water molecules to xylem walls
Transpiration pull generated by evaporation from leaves
The cohesion-tension theory explains the upward movement of water in plants. Which of the following is NOT a critical component of this theory?
Cohesion of water molecules
Adhesion of water molecules to xylem walls
Transpiration pull creating negative pressure
Active transport of water into xylem by root cells
The cohesion-tension theory explains the ascent of sap in the xylem primarily due to:
Root pressure
Capillary action
Active transport of water
The cohesive properties of water and transpiration pull
Which force is primarily responsible for imbibition?
Gravitational forces
Cohesive forces
Adhesive forces
Osmotic pressure
The cohesion-tension theory explains the ascent of sap in plants. The 'cohesion' part of this theory refers to:
The attraction between water molecules and xylem walls
The attraction between water molecules
The evaporation of water from the leaf surface
The active transport of water into the xylem
Which of these processes helps in the upward movement of water during transpiration?
Diffusion
Osmosis
Cohesion and adhesion
Active transport
Which of the following BEST explains why the ascent of sap in tall trees is primarily attributed to the cohesion-tension theory rather than root pressure?
Root pressure only operates during the night
Root pressure is primarily involved in nutrient transport, not water transport
Root pressure alone cannot generate sufficient pressure to overcome the gravitational force in tall trees
The cohesion-tension theory is more energy-efficient than root pressure
The column of water within xylem vessels of tall redwood trees can reach remarkable heights without breaking. What primary property of water contributes to this phenomenon?
Adhesion
Surface tension
High density
Cohesion
Imagine a thin glass tube dipped in water. The water rises in the tube due to adhesion. In tall trees, a similar phenomenon helps maintain the water column, but a different property of water plays the major role in preventing the column from breaking under its own weight. What is this property?
Capillary action
High specific heat
Low viscosity
Cohesion
