Prepare for NEET with Botany-specific practice questions. Covering all major Botany chapters, this is perfect for your NEET Biology needs.
A researcher observes that water absorption by roots is significantly reduced when the plant is treated with a respiratory inhibitor. Which of the following best explains this observation?
Respiratory inhibitors directly block aquaporin function, preventing water movement.
Respiration is essential for maintaining root cell turgidity, which is directly linked to water absorption.
Active transport of ions into the root cells requires energy, creating a water potential gradient that drives water uptake.
Inhibition of respiration disrupts the cohesion-tension theory, preventing water movement through the xylem.
The guttation phenomenon observed in some plants is primarily driven by:
High transpiration rates during the day.
Active transport of water into the xylem by xylem parenchyma.
Root pressure exceeding transpiration pull, particularly at night.
Capillary action in the xylem vessels.
Guttation in plants is primarily caused by:
Root pressure exceeding transpiration pull
High transpiration rates during the day
Opening of stomata at night
Active transport of water into xylem vessels
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
Under which of the following specific environmental conditions would guttation be LEAST likely to occur?
Cool, humid night with high soil moisture
Warm, humid morning with adequate soil moisture
Cool, dry night with moderate soil moisture
Hot, dry day with low soil moisture
If the water potential of root cells is -0.5 MPa and the water potential of the xylem sap is -0.7 MPa, which statement BEST describes the movement of water?
Water will move from the xylem into the root cells
Water will move from the root cells into the xylem
There will be no net movement of water
Water will move equally in both directions
Which of the following experimental manipulations would MOST effectively demonstrate the contribution of root pressure to xylem sap ascent in a small herbaceous plant?
Submerging the roots in a hypertonic solution and observing changes in leaf turgor
Measuring the rate of transpiration under varying light intensities
Removing the apical bud and observing the effect on guttation
Measuring exudation rate from a cut stem stump after applying a respiratory inhibitor to the roots
A plant exhibits vigorous guttation during the night. Which of the following would be the MOST likely consequence of completely sealing the hydathodes with a waterproof sealant without harming the plant otherwise?
A significant decrease in root pressure
A substantial increase in transpiration rate
No change in root pressure or transpiration rate
A slight increase in root pressure
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.
Guttation in plants is mainly due to:
Transpiration
Root pressure
High humidity
Low temperature
