Prepare for NEET Biology Transport in Plants with MCQs & PYQs on NEET.GUIDE. Access free practice, previous year questions, and expert guidance to understand xylem, phloem, and movement of water.
A plant cell with a water potential of -0.65 MPa is placed in a solution with a water potential of -0.30 MPa. Assuming the cell wall is rigid and fully permeable, and the cell membrane is selectively permeable, what will be the pressure potential of the cell at equilibrium?
-0.95 MPa
-0.35 MPa
+0.35 MPa
+0.95 MPa
A researcher observes that a particular plant cell placed in a solution exhibits incipient plasmolysis. If the solute potential of the cell is -1.2 MPa, what is the MOST likely water potential of the surrounding solution?
-1.2 MPa
-1.0 MPa
-1.4 MPa
-0.8 MPa
A plant cell is placed in a solution with a water potential of -0.8 MPa. The cell's initial solute potential is -1.2 MPa and its pressure potential is 0.4 MPa. After equilibration, which of the following statements about the cell's state is MOST accurate?
The cell will be turgid, with a pressure potential greater than 0.4 MPa.
The cell will be flaccid, with a pressure potential of zero.
The cell will be plasmolyzed, with a pressure potential of zero.
The cell will experience incipient plasmolysis, with a pressure potential slightly above zero.
Imagine a plant cell undergoing plasmolysis. If the external solution's water potential is further decreased, which of the following is the MOST likely consequence?
Deplasmolysis and return to a turgid state.
Incipient plasmolysis with the cell membrane just touching the cell wall.
No further change in the cell's state.
Increased plasmolysis with further shrinkage of the protoplast.
A plant cell with a water potential of -0.6 MPa is placed in a solution. After a period of time, the cell reaches equilibrium and is found to be plasmolyzed. Which of the following values could represent the water potential of the solution?
-0.4 MPa
-0.6 MPa
-0.8 MPa
-0.2 MPa
If dry wooden blocks are placed in a solution with a solute potential of -0.5 MPa, and the initial water potential of the wood is -2.0 MPa, which of the following will occur?
Water will move from the solution into the wooden blocks.
Water will move from the wooden blocks into the solution.
No net movement of water will occur.
The wooden blocks will dissolve in the solution.
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.
Which of the following scenarios would result in the LEAST efficient water absorption by a plant's roots?
Slightly acidic soil with optimal nutrient availability
Well-aerated soil with moderate water content
Low soil temperature coupled with high humidity
High soil salinity coupled with low soil oxygen levels
The pressure-flow hypothesis explains the translocation of sugars in the phloem. Which of the following statements regarding this hypothesis is INCORRECT?
Active loading of sugars at the source creates a high solute concentration in the sieve tubes.
Water moves from the xylem to the phloem at the source, increasing turgor pressure.
Sugars are unloaded at the sink, lowering the solute concentration and water potential.
Water moves from the sink to the source via the phloem, driven by a pressure gradient.
A plant cell with a water potential of -0.6 MPa is placed in a solution with a water potential of -0.8 MPa. Which of the following will occur?
Water will move out of the cell, causing plasmolysis.
Water will move into the cell, causing turgor pressure to increase.
There will be no net movement of water.
The cell will burst due to excessive water uptake.
