Root pressure develops due to
1. active absorption
2. low osmotic potential in soil
3. passive absorption
4. increase in transpiration
Which of the following criteria does not pertain to facilitated transport?
1. Requirement of special membrane proteins
2. High selectivity
3. Transport saturation
4. Uphill transport
Which one of the following elements in plants is not remobilised?
1. Calcium | 2. Potassium |
3. Sulphur | 4. Phosphorus |
The rupture and fractionation do not usually occur in the water column in vessel/tracheids during the ascent of sap because of
1. lignified thick walls
2. cohesion and adhesion
3. weak gravitational pull
4. transpiration pull
Passage cells are thin-walled cells found in:
1. endodermis of roots facilitating rapid transport of water from cortex to pericycle
2. phloem elements that serve as entry points for substances for transport to other plant parts
3. testa of seeds to enable emergence of growing embryonic axis during seed germination
4. central region of style through which the pollen tube grows towards the ovary
Two cells A and B are contiguous. Cell A has osmotic pressure 10 atm, turgor pressure 7 atm and diffusion pressure deficit 3 atm. Cell B has osmotic pressure 8 atm, turgor pressure 3 atm and diffusion pressure deficit 5 atm. The result will be
1. Movement of water from cell B to A
2. No movement of water
3. Equilibrium between the two
4. Movement of water from cell A to B
The translocation of organic solutes in sieve tube members is supported by:
1. root pressure and transpiration pull
2. P-proteins
3. mass flow involving a carrier and ATP
4. cytoplasmic streaming
Wooden doors swell up and get stuck during the rainy season. This is due to the phenomenon of
1. imbibition
2. endosmosis
3. capillarity
4. deplasmolysis.
In plants, water moves from
1. less negative to more negative potential
2. more negative to less negative potential
3. a point to another point with the same potential
4. none of the above
If turgor pressure becomes equal to the wall pressure, then
1. water leaves the cell
2. water enters the cell
3. no exchange of water takes place
4. solute goes from the cell into water