According to the mass flow hypothesis:
(a) Sucrose is moved into the companion cells and then into the sieve tube by passive transport.
(b) Inside the phloem, an osmotic pressure gradient is generated that facilitates the mass movement in the phloem.
(c) Water in the adjacent xylem moves into the phloem by an active process.

1. (a) and (c) are correct.
2. (b) and (c) are incorrect.
3. (a) and (c) are incorrect.
4. (a) and (b) are correct.

Select the correct statement with respect to given statements

1. Water transport is related with transpiration and
guttation is related to stomata.

2. Transpiration is passive process but opening of
stomata is active.

3. C₃ plants are twice efficient in photosynthesis
as compared to C₄ plants whereas C₃ plants are
less efficient with respect to transpiration than C₄ plants.

4. Minerals uptake is passive whereas water
absorption is active.

Osmotic pressure of a solution is
1. more than that of pure solvent
2. less than that of pure solvent
3. variable depending upon concentration
4. equal to that of pure solvent

The continuous excretion of watery substance
from stump of a well-watered potted plant after
cutting off the shoot slightly above the base is
due to
1. root pressure

2. guttation

3. transpiration

4. imbibitions

When a cell is placed in a solution whose osmotic concentration is equal to cell sap then:

1. Water moves inside the cell.

2. Water moves outside the cell.

3. No net movement of water occurs.

4. Cell will be plasmolysed.

I. Phloem sap can be transported in any required direction.
II. Phloem transports mainly water and sucrose but other sugars, hormones, and amino acids are also transported.
III. Cytoplasmic strands pass through the holes in the sieve plate forming continuous filaments.
IV. Ascent of sap is a pulling movement and the translocation of organic solutes is a pushing movement.

1. All are correct
2. All are incorrect
3. I, II, III are correct
4. III and IV are correct

How many of the following statements are correct?
(i) In plants each organ receiving some substances & giving out some others.
(ii) Water channels are made up of eight different types of aquaporins.
(iii) Water is often a limiting factor for plant growth & productivity in both agricultural & Natural environments.
(iv) Imbibition is also diffusion.

Options:
1. All the above
2. (i), (ii) & (iv)
3. (ii), (iii) & (iv)
4. (iii) & (iv)

In the xylem, a continuous chain of water, when it is broken, is re-established by:
1. Guttation
2. Root pressure
3. Imbibition
4. Transpiration

The interconnected cells which do not show symplastic movement of water are:

1. Mesophyll cells
2. Tracheids
3. Xylem parenchyma cells
4. Cells of endodermis

The water potential of pure water at standard temperatures, which is not under any pressure is taken to be equivalent to
1. Zero
2. –${\mathrm{\psi }}_{\mathrm{S}}$
3. ${\mathrm{\psi }}_P$
4. +${\mathrm{\psi }}_{\mathrm{S}}$