Biology · Continuity and change

D2.3 — Water potential

Biology · SL / HL · syllabus-mapped notes

1. D2.3.1

   Solvation with water as the solvent

   Explain solvation, and why water's polarity makes it a good solvent.

2. D2.3.2

   Water movement from less concentrated to more concentrated solutions

   Explain net water movement, and define hypotonic, hypertonic and isotonic.

3. D2.3.3

   Water movement by osmosis into or out of cells

   Explain osmosis across a membrane, and how cells can change its rate and direction.

4. D2.3.4

   Changes due to water movement in plant tissue bathed in hypotonic and those bathed in hypertonic solutions

   Investigate water movement in plant tissue bathed in solutions of different concentration.

5. D2.3.5

   Effects of water movement on cells that lack a cell wall

   Explain what happens to cells without a cell wall in hypotonic and hypertonic solutions.

6. D2.3.6

   Effects of water movement on cells with a cell wall

   Explain turgor, flaccidity and plasmolysis in cells with a cell wall.

7. D2.3.7

   Medical applications of isotonic solutions

   Explain why isotonic solutions are used in medical procedures.

8. D2.3.8

   Water potential as the potential energy of water per unit volume

   Define water potential, and state the two contributors that vary in living systems.

9. D2.3.9

   Movement of water from higher to lower water potential

   Explain why water moves from higher to lower water potential, and read negative values correctly.

10. D2.3.10

    Contributions of solute potential and pressure potential to the water potential of cells with walls

    Explain solute potential and pressure potential, and their possible signs.

11. D2.3.11

    Water potential and water movements in plant tissue

    Explain water movement in plant tissue bathed in hypotonic and hypertonic solutions.