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Course: AP??/College Biology?>?Unit 2

Lesson 7: Mechanisms of transport: tonicity and osmoregulation

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Mechanisms of transport: tonicity and osmoregulation

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A group of biology students weighed several potato cubes and placed them in open beakers containing various sucrose solutions at

30^{°} C

. The following day, the students weighed the potato cubes again and calculated the differences in mass.

It was determined that solute potential equilibrium was reached at

0.35 M

.

Solute potential of a solution:

ψ_{s} = ? i C R T

$i =$ ? ionization constant ( $1.0$ ? for sucrose)
$C =$ ? molar concentration
$R =$ ? pressure constant ( $0.0831 L ? bar ? {mol}^{? 1} ? K^{? 1}$ ?)
$T =$ ? temperature in Kelvin ( $^{°} C$ ? of solution $+ 273$ ?)

What is the solute potential of the potato cubes?

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