Diffusion is very important to plants since:
1. The cells have a permeable cell wall
2. It is the only means for gaseous movement within the plant body.
3. Plants cannot transport material by active transport.
4. They are unable to move towards the source of the nutrients.
Which of the following is not a characteristic of facilitated transport in plants?
1. Requirement of special membrane proteins
2. Being non-selective
3. Transport saturates
4. It is a downhill transport
If a pressure greater than atmospheric pressure is applied to a solution, its water potential:
1. Increases
2. Decreases
3. Remains the same
4. Becomes zero
For imbibition to occur the pre-requisites is/are:
i. Water potential gradient between the adsorbent and the liquid imbibed.
ii. Affinity between the adsorbent and the liquid imbibed.
1. Only i
2. Only ii
3. Both i and ii
4. Neither i nor ii
Water movement in plants is:
1. Down a potential gradient in apoplast and up the potential gradient in symplast
2. Down a potential gradient in symplast and up the potential gradient in apoplast
3. Up the potential gradient in both apoplast and symplast
4. Down the potential gradient in both apoplast and symplast
What percent of water reaching them is used by leaves in photosynthesis?
1. Less than 1%
2. About 5 %
3. About 5 % in warm conditions and about 10 % in cold conditions
4. About 50 %
Attraction of water molecules to polar surfaces [such as the surface of tracheary elements] is called as:
1. Connation
2. Adnation
3. Cohesion
4. Adhesion
Which one is incorrectly matched pair
1. Lenticular transpiration – Approximately 0.1% of total water loss.
2. Direction of movement – Low DPD to of water high DPD.
3. w of pure water – Minimum.
4. w (solute potential) – Lowering of free energy of water.
The direction of movement of water in given cells A, B and C can be represented as
1.
2.
3.
4.
For a solution at atmospheric pressure
1.
2.
3.
4.
At the sink, sucrose is moved out of the phloem sap by .....A..... , as a result the osmotic pressure ....B.... in sieve tube elements.
Fill the blanks with suitable A and B.
A B
1. Active transport Increases
2. Active transport Decreases
3. Passive transport Increases
4. Passive transport Decreases
solutes and allow the passage of ions in one direction only?
1. Epiblema.
2. Endodermis.
3. Pericycle.
4. Cortex.
Potometer is a device used for measuring rate of
1. Imbibition.
2. Ascent of sap.
3. Transpiration.
4. Phloem transport.
If pressure greater than atmospheric pressure is applied to two medium one having pure water (A) and another having solution (B), then what would be effect on water potential
Pure water (A) Solution (B)
1. Increase Increase
2. No change Increase
3. No change Decrease
4. Decrease Decrease
Transport of food material takes place via sieve tube, continuity between these tubes are maintained by ?
1. Plasmodesmata.
2. Cytoplasmic strands.
3. Companion cell.
4. Phloem parenchyma.
Which of the following statements does not apply to reverse osmosis?
1. It is used for water purification.
2. In this technique, pressure greater than osmotic pressure is applied to the system.
3. It is a passive process.
4. It is an active process.
Which one of the following will not directly affect transpiration?
1. Temperature.
2. Light.
3. Wind speed.
4. Chlorophyll content of leaves
The process of guttation takes place
1. When the root pressure is high and the rate of transpiration is low.
2. When the root pressure is low and the rate of transpiration is high.
3. When the root pressure equals the rate of transpiration.
4. When the root pressure as well as rate of transpiration are high.
What happens, when a cell is placed in a isotonic solution?
(a) There is not net flow of water towards the inside or outside.
(b) Cells are said to be flaccid.
(c) becomes positive.
(d) Enlargement and extension growth of cells occur.
The correct statement(s) is/are
1. a only
2. a and b only
3. a, b and c only
4. all are correct
Exchange of gases between the outer atmosphere and the internal tissue of the woody stem is possible by
1. Hydathaodes.
2. Lens shaped openings.
3. Stomata.
4. Gas vacuoles.
Facilitated transport differs from active transport as the former
1. Transports saturates.
2. Response to protein inhibitors.
3. Requires special membrane proteins.
4. Shows downhill transport.
Statement-1: Xylem transport can be unidirectional and bidirectional.
Statement-2: Both phloem loading and unloading is active process.
Options
1. Both statements are correct.
2. Both statements are incorrect.
3. 1 is correct, 2 is incorrect.
4. 1 is incorrect, 2 is correct.
Find the direction of water flow in the given system
1. A C
2. BC
3. C A
4. A B
Loss of water in liquid phase from the margin of leaves in many herbaceous plants is/occurs
1. Guttation
2. Transpiration
3. At noon
4. Due to cohesion-tension model of water movement.
Two factors, which affect water potential, are
1. Amount of solutes and external pressure
2. Amount of solutes and internal pressure
3. Amount of sodium and wall pressure
4. All of these