Osmotic potential and water potential of pure water are respectively:
1.  0 and 0
2.  0 and 1
3.  100 and 0
4.  100 and 100

What shall be the water potential of a root hair cell absorbing water from the soil?
1.  Zero
2.  Less than zero
3.  More than zero
4.  Infinite

When a freshwater protozoan possessing a contractile vacuole, is placed in a glass containing marine water, the vacuole will:

1. Disappear

2. Increase in size

3. Decrease in size

4. Increase in number