Tag: plant water relation

Quizzes (6) Questions (146)

Questions Related to plant water relation

Multiple choice water potential water potential and pressure plant water relation transport in plants biology

Cell A and cell B are adjacent plant cells. In cell A, $\psi s$ = - 20 bars and $\psi _p$ = 8 bars. In cell B, $\psi _s$ = - 12 bars and $\psi _p$ = 8 bars. Then ______________.

  1. Water moves from cell A to cell B

  2. There is no movement of water between cell A and cell B

  3. Water moves from cell B to cell A

  4. Equal amount of water is simultaneously exchanged between cell A and cell B
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Water potential (Psi_w) = Psi_s + Psi_p. For cell A: -20 + 8 = -12 bars. For cell B: -12 + 8 = -4 bars. Water moves from higher potential (-4) to lower potential (-12), so from B to A.

Multiple choice water potential water potential and pressure plant water relation transport in plants biology

What is the effect on the value of DPD when the water potential of that cell is increased :-

  1. No effect

  2. Increase

  3. Decrease

  4. Firstly increase then decrease
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Diffusion Pressure Deficit (DPD) is inversely related to water potential (DPD = -Psi_w for standard solutions without external pressure). Therefore, when the water potential of a cell increases, its DPD decreases.

Multiple choice water potential water potential and pressure plant water relation transport in plants biology

0.5 M sucrose develops a pressure of 15 bars  in an osmometer. Which of the following statement is wrong for such a solution ______________.

  1. That its osmotic potential is-15 bars

  2. That its water potential is-15 bars

  3. That its pressure potential is-15 bars

  4. That its osmotic potential is+15 bars
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The pressure potential is usually positive.

So the incorrect option is C.

Multiple choice water potential water potential and pressure plant water relation transport in plants biology

Pick the CORRECT statement(s) in the following.
I. Increase in solute potential of a solution increases its water potential.
II. Water potential of pure water is taken as zero.

  1. I only

  2. II only

  3. Both (I) & (II)

  4. Neither (I) nor (III)
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Statement I is correct because increasing solute potential (making it less negative or adding positive increments) increases water potential. Statement II is correct because pure water at standard temperature and pressure has a water potential defined as zero.

Multiple choice water potential water potential and pressure plant water relation transport in plants biology

Two cells are kept in $1\ M$ solution of sucrose and $1\ M$ solution of $NaCl$. The water potential $(\Psi {m})$ of the cells kept in _______________.

  1. sucrose solution will be greater
  2. $NaCl$ solution will be greater

  3. both will be equal
  4. sucrose solution will be lower and $NaCl$ solution would be greater
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

NaCl dissociates into two ions (Na+ and Cl-), while sucrose does not. Therefore, 1 M NaCl has a lower (more negative) solute potential than 1 M sucrose. Consequently, the water potential of the cell in sucrose solution will be greater.

Multiple choice water potential water potential and pressure plant water relation transport in plants biology

The concentration of solute in four cells iis 0.4 M. They are placed in four separate containers I, II, III and IV, filled with saline water of concentrations 0.1 M, 0.4 M, 2 M, and 3 M respectively. In which container will the cell swell? 

  1. I

  2. II

  3. III

  4. IV
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The cell will swell when the concentration of solute is more inside the cell than the surrounding. Here the concentration of solute inside the cell is 0.4 M, and out of given solutions, 0.1 M solution has a lesser concentration of solute. So, the cell which is placed in a 0.1 M solution will swell. This phenomenon is called osmosis.


So the correct answer is 'A'.

Multiple choice water potential water potential and pressure plant water relation transport in plants biology

Water will move from the root hair through cortex if the water potentials are _________________________.

  1. Root hair- $0$, Cortex-$0$, Xylem-$0$
  2. Root hair-$-2$, Cortex-$-1$, Xylem-$0$
  3. Root hair-$0$, Cortex-$-1$, Xylem-$-2$
  4. Root hair-$0$, Cortex-$+1$, Xylem-$+2$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

If a difference in water potential exists between the two regions, spontaneous movement of water will take place, provided the movement can occur between them. The direction of flow will be energetically down hill, that is from the region of higher water potential(root hair) to the region of lower water potential(xylem) via cortex from less negative water potential (e.g., - $1$ kPa) to more negative water potential (e.g., - $2$ kPa).

So, the correct answer is 'Root hair-0,, Cortex-−1, Xylem−2'

Multiple choice water potential water potential and pressure plant water relation transport in plants biology

Read the following statements and select the correct option.


(i) Pure water has the highest water potential, i.e., zero.
(ii) Process of diffusion does not require any input of energy.
(iii) Water moves from the system containing water at higher water potential to the one having lower water potential.

  1. Statements (i) and (ii) are correct

  2. Statements (ii) and (iii) are correct

  3. Statements (i) and (iii) are correct

  4. Statements (i), (ii) and (iii) are correct
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Pure water is with no dissolved solutes hence its potential is highest that is zero, as solute is added to water potential or energy of water becomes negative. Diffusion is movement of substances from their higher potential/energy/concentration to places of lower potential /energy/concentration hence does not require in put of energy.

Water always moves from its higher potential i.e with lower solute potential to its lower potential or higher solute potential by a process called osmosis.
So, the correct answer is 'Statements (i), (ii) and (iii) are correct'