The ions that plays the primary role in basic transport processes in plant cells is:
1. ${\mathrm{Na}}^{+}$
2. ${\mathrm{K}}^{+}$
3. ${\mathrm{H}}^{+}$
4. ${\mathrm{Cl}}^{-}$

Osmosis in plants would not be affected by:
1. water potential gradient
2. a difference in solute concentrations
3. type of cell membrane receptor proteins
4. number of aquaporins

Active transport of substances does not involve:
1. transport of solute along the concentration gradient.
2. use of a specific membrane transport protein.
3. hydrolysis of ATP.
4. transport of solute against a concentration gradient.

The proton pump in the plasma membrane of a plant cell does not:
1. hydrolyze ATP
2. establish a proton gradient across the membrane
3. generate a membrane potential
4. equalize the charge on each side of a membrane

The direction of water movement in plants can always be predicted by measuring:
1. pressure potential
2. number of aquaporins
3. proton gradients
4. water potential (ψ)

The water potential (Ψ) of pure water in a container open to atmosphere under standard conditions is:
1. -0.1 MPa.
2. +0.1 MPa.
3. +0.5 MPa.
4. 0.0.

Water potential (Ψ) in plants is affected by:
I. mechanical pressure.
II. matrix effects (e.g., fluid cohesion and surface tension).
III. dissolved solutes.
IV. osmosis.
1. I, II and III only
2. I, III and IV only
3. II, III and IV only
4. I, II, III and IV

Give ${\mathrm{\psi }}_{\mathrm{P}}$ = 0.25 MPa and ${\mathrm{\psi }}_{\mathrm{S}}$ = -0.50 MPa,what will be the resulting Ψ:
1. +0.75 MPa.
2. -0.75 MPa.
3. -0.25 MPa.
4. +0.25 MP

The water potential [Ψ] in root tissue was found to be -0.13 MPa. The Ψ of 0.1 M solution of sucrose is -0.23. If the root tissue is placed in this solution, the net water movement is expected to be
1. from the root tissue into the sucrose solution.
2. from the sucrose solution into the root tissue.
3. equal in both direction.
4. requiring ATP hydrolysis for either direction.

A cell has less number of aquaporins when compared to another cell in a plant. With respect to the latter cell, the former cell will have:
1. a faster rate of osmosis.
2. a lower water potential.
3. a higher water potential.
4. a lower rate of osmosis.