D2.3 Water Potential

Question 1

Water potential

Answer 1

The pressure exterted by water molecules when they collide with a container or.a membrane

Measured in kPa; Ψ (Psi)

Question 2

Solute Potential

Answer 2

The contribution solute makes to the water potential of a solution
* the greater the solute potential the lower the water potential

Because the more solute = the less water

Question 2

How water potential works

Answer 2

• pure water has the highest water potential at 0kPa (standard temp & pressure; 25 degrees, 100kPa)
• solutions have lower water potential than pure water = always negative

Question 2

Pressure Potential

Answer 2

The contribution pressure makes to the water potential of a solution
* the greater the pressure the greater the water potential

Question 3

Water Potential equation

Answer 3

ΨW = ΨS + ΨP

Question 4

Hypertonic

Answer 4

higher concentration then cells cytoplasm => water leaves cell

Question 5

Hypotonic

Answer 5

Lower concentration then cells cytoplasm => water enters cell

Question 6

Isotonic

Answer 6

Same concentration as cells cytoplasm
=> cell stays normal

Question 8

Plasmolysis

Answer 8

The shrinking of the cytoplasm away from the cell wall of a plant or bacteria

Question 9

Contractile Vacuole

Answer 9

Prevents cell lsis as it takes in water during osmoregulation

Question 10

Lysis

Answer 10

too much water flows into cell causing it to burst under turgor pressure