The primary mechanism for xylem sap ascent in tall trees is transpiration pull. However, root pressure plays a minor role. Which statement BEST describes the limited contribution of root pressure to overall xylem sap ascent in tall trees?
Root pressure generates excessive pressure that could damage the delicate xylem tissues in tall trees.
Root pressure is only active during the night and therefore cannot contribute to daytime transpiration.
Tall trees have a significantly lower root surface area to volume ratio, minimizing the contribution of root pressure.
Root pressure can only push water a limited height due to the opposing force of gravity and the relatively low pressure generated.
Related Questions
Guttation is mainly due to
Root pressure
Imbibition
Osmosis
Transpiration
A researcher applies a potent respiratory inhibitor to the root cells of a plant. Which of the following would be MOST directly affected, ultimately impacting root pressure?
Water potential gradient between the soil and root hairs
Cohesion and adhesion of water molecules in the xylem
Transpiration pull from the leaves
Active transport of ions into the xylem
Which of the following processes explains the appearance of water droplets on the margins of leaves of a small herbaceous plant during a humid night?
Transpiration
Respiration
Guttation
Photosynthesis
The primary reason for a passive flow of water from soil into the atmosphere through the plant body is?
Cohesive forces
Adhesive forces
Tension
Water potential gradient
The term root pressure was coined by?
S.Hales
Dixon
Levitt
Bose
Cohesion theory of water movement in plants was put forth by
Melvin cycle
F F Blackman
T W Engelmann
Henry Dixon
Water vapor exits and carbon dioxide enters a plant leaf through stomata. Which process explains this two-way movement of gases?
Active transport
Osmosis
Transpiration pull
Diffusion
Water lost in Guttation is
Pure water
liquid droplets
In vapour form
Either (A) or (B)
Examples of bulk flow by a positive hydrostatic pressure gradient and a negative hydrostatic pressure gradient are
Suction through straw and swelling of wood, respectively
Imbibition and a garden hose
Garden hose and suction through a straw, respectively
Swelling of wood and imbibition, respectively
Guttation, the exudation of water droplets from leaves, is most likely to occur when:
Root pressure is low and transpiration is high.
Root pressure is high and transpiration is high.
Root pressure is low and transpiration is low.
Root pressure is high and transpiration is low.
