An experiment was undertaken to test the permeability of the plasma membrane and tonoplast of beetroot cells in various different chemicals. Vacuoles of beetroot cells carry a red pigment which cannot diffuse through their plasma membranes and tonoplasts to leave the cell.
The beetroot was cut into equal 1 cm3 cubes before being washed under a tap for 15 seconds to remove pigment released from outer damaged cells. The cubes were then placed in the various solutions, all of which turned red.
The table below shows four possible behaviors of phospholipids and proteins in different solutions, which is correct?
|
solution |
protein denatures |
solution |
phospholipids dissolve |
A
B
C
D
|
ethanol
50°C water
ethanol
dilute HCl
|
✓
✓
✓
✓
|
dilute HCl
ethanol
50°C water
dilute HCl
|
✓
✓
✓
✓
|