On a warm summer day, the transpiration pull is the main force that drives from root parenchyma into the root xylem. The table shows values of $ψ_{p}$ (pressure potential) and $ψ_{s}$ (solute potential) in root xylem and root parenchyma, in kPa. In which of the options (a-d) would transpiration pull cause water to move from root parenchyma into the root xylem?

Root parenchyma
Root xylem
$ψ_{p}$ $ψ_{s}$ $ψ_{p}$ $ψ_{s}$
(a) $200$ $- 190$ $- 200$ $5$
(b) $- 200$ $220$ $65$ $- 5$
(c) $200$ $- 220$ $65$ $- 5$
(d) $200$ $- 220$ $- 65$ $- 5$

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

Open in App

Solution

The correct option is D D
10 -195
20 60
-20 60
-20 75
The formula used here is Ψw= Ψp+Ψs
Movement of water takes place from less negative water potential to more negative water potential.
Movement of water from root parenchyma into root xylem will occur in the first case because here water moves from less negative water potential (10) to more negative water potential (-195).

So the correct option is "A".

Suggest Corrections

Similar questions

Two cells, A and B beside each other in the root cortex. $ψ_{s}$ and $ψ_{p}$ values of cell A are - 0.8 MPa and 0.6 MPa. $ψ_{s}$ and $ψ_{p}$ of cell B are -0.7MPa and 0.4 MPa. Water moves from ______.

Q. 'A' and 'B' are two adjacent living cells. The cell 'A' has solute potential

(Ψ_{s})

of
-9 bars and pressure potential

(Ψ_{p})

of 4 bars, whereas cell 'B' has solute potential

(Ψ_{s})

of
-8 bars and pressure potential

(Ψ_{p})

of 5 bars. What will be the direction of water movement between these cells?

There are 2 adjacent living cells A & B. The cell ‘A’ has osmotic potential ( $Ψ$ s) of - 7 bars, and pressure potential ( $Ψ_{p}$ ) of 5 bars, whereas cell ‘B’ has osmotic potential ( $Ψ_{s}$ ) of – 8 bars and pressure potential ( $Ψ_{p}$ ) of 3 bars, what will be the direction of water flow in these cells?

Q. Solution A has

Ψ_{s} = - 30

bars and

Ψ_{p} = 5

bars. Solution B has

Ψ_{s} = - 10

bars and

Ψ_{p} = 0

atm. The two are separated by semipermeable membrane. Flow of water will be

Q. X and Y are two living cells adjacent to each other. The cell X has solute potential

(Ψ_{s})

of -9 bars and pressure potential

(Ψ_{p})

of 4 bars whereas cell Y has solute potential

(Ψ_{s})

of -8 bars and pressure potential

(Ψ_{p})

of 5 bars. What will be the direction of water movement between these cells?

Join BYJU'S Learning Program

Root parenchyma		Root xylem
$ψ_{p}$	$ψ_{s}$	$ψ_{p}$	$ψ_{s}$
(a) $200$	$- 190$	$- 200$	$5$
(b) $- 200$	$220$	$65$	$- 5$
(c) $200$	$- 220$	$65$	$- 5$
(d) $200$	$- 220$	$- 65$	$- 5$