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

Casparian bands are found in:

The movement of ions against the concentration gradient will be:

Opening and closing of stomata are due to the:

1. Hormonal change in guard cells

2. Change in Turgor pressure of guard cells

3. Gaseous exchange

4. Respiration

Stomata of a plant open due to:

1. Influx of potassium ions

2. Efflux of potassium ions

3. Influx of hydrogen ions

4. Influx of calcium ions

Loading of phloem is related to:
1.  Increase of sugar in phloem
2.  Elongation of phloem cell
3.  Separation of phloem parenchyma
4.  Strengthening of phloem fiber

When water moves through a semipermeable membrane then which of the following pressure develops:
1.  O.P.
2.  S.P.
3.  T.P.
4.  W.P.

Glycolate induces the opening of stomata when: 
1.  Presence of oxygen
2.  Low $C{O}_2$ conc.
3.  High $C{O}_2$
4.  $C{O}_2$ absent

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 

A cell 'A' with D.P.D. = 8 is surrounded by three cells 'B', 'C' and 'D' with D.P.D. respectively 4, 6 and 5. What shall be the direction of water movement?

1. $B\to A\leftarrow C$
$$ $$ $$ $$ $$ $$ $$ $\uparrow$
$$ $$ $$ $$ $$ $$ $$ $D$
2. A → B → C → D
3. D → C → B ← A
4. A → B ← C → D