Water Potential

What is Water PotentialRead paragraph 2

Term used by botanists when predicting the movement of water into or out of plant cells (walled; have more pressure differences)

Has two components:• Pressure potential (p): The physical pressure

component of system.• Solute potential (s): The effect of solute

concentration on system.

Calculating water potential (

psWater Potential = pressure pot. + solute pot.

Understanding Water Potential(read paragraphs 3 &4)

Water will always move from High to low

Pure water in an open system at atmospheric pressure has a p = 0

This makes s

Cause Effect

Understanding Water Potential(read paragraph 7)

s is always negative.Pure water = 0, therefore adding solute lowers

(more negative)Draw cell in solution to compare in two

different areas. Will always assume that solute is NOT diffusing !

Purpose

• We will determine the water potential of russet potatoes, Yukon gold potatoes, Yams, and carrots by measuring their sucrose(solute) concentrations to see if they differ.

• Hypothesis:

Lab ReportIntro:• Purpose• HypothesisResults:• Graph Average % Change in mass for potatoes• Data Table for average sucrose molarities of each potato, and

calculated Conclusion:• Hypo supp/rej• Data to justify this • Questions 7,8,9 (hand written)