D2.3 Water potential (Cells): Practice Questions

• a.

  Solute concentration and temperature

• b.

  Solute potential (\(\Psi_S\)) and pressure potential (\(\Psi_P\))

• c.

  Osmotic pressure and gravity potential

• d.

  Turgor pressure and wall elasticity

• a.

  \(-0.6\text{ MPa}\)

• b.

  \(-0.3\text{ MPa}\)

• c.

  \(0.6\text{ MPa}\)

• d.

  \(-1.2\text{ MPa}\)

• a.

  \(+1.6\text{ MPa}\)

• b.

  \(+0.8\text{ MPa}\)

• c.

  \(-1.6\text{ MPa}\)

• d.

  \(-0.8\text{ MPa}\)

• a.

  Water moves from a region of lower water potential to a region of higher water potential.

• b.

  Water moves from a more negative water potential to a less negative water potential.

• c.

  Water moves from an area of high solute concentration to an area of low solute concentration.

• d.

  Water moves from a region of higher water potential to a region of lower water potential.

• a.

  Water will enter the cell until the pressure potential is equal to \(+1.1\text{ MPa}\).

• b.

  Solutes will move into the cell until the internal water potential reaches \(-1.1\text{ MPa}\).

• c.

  Water will leave the cell by osmosis, causing the cell membrane to pull away from the cell wall.

• d.

  There will be no net movement of water because the water potential is negative in both systems.

Write your answer out first, then check it against the worked solution.