Plant-water relations - water potential transpiration ascent of sap - Question Bank
1. The movement of water into a plant cell from a hypotonic solution is driven by:
2. Which of the following is a major component of the apoplast pathway?
3. The rate of transpiration is directly proportional to:
4. If the solute potential (Ψs) of a cell is -0.7 MPa and the pressure potential (Ψp) is +0.4 MPa, what is the water potential (Ψw) of the cell?
5. Which of the following is a characteristic of xylem tissue that aids in water transport?
6. The phenomenon of guttation is most likely to occur:
7. During heavy rainfall, the water potential of the soil generally:
8. What is the term for the potential energy of water per unit volume due to pressure?
9. The movement of water from one cell to another through plasmodesmata is part of the:
10. Which of the following is a consequence of excessive transpiration?
11. The pressure potential (Ψp) in a turgid plant cell is typically:
12. Which phenomenon is responsible for the 'negative pressure' or 'pull' in the xylem that draws water upwards?
13. If a plant cell has a water potential of -0.5 MPa and its surrounding solution has a water potential of -0.2 MPa, water will move:
14. What is the role of guard cells in transpiration?
15. The main driving force for the movement of water into root hairs from the soil is:
16. Xylem vessels are composed of dead cells and are essentially hollow tubes. This structural feature facilitates:
17. The phenomenon where water moves across a semipermeable membrane from a region of lower solute concentration to a region of higher solute concentration is called:
18. When a plant is under water stress, stomata tend to:
19. The water potential of a cell is determined by the sum of its:
20. A decrease in turgor pressure in a plant cell leads to:
21. Which of the following is NOT a mechanism that aids in the ascent of sap?
22. The loss of water vapour from aerial parts of plants, primarily through stomata, is known as:
23. What is the primary function of xylem in plants?
24. The Casparian strip in the endodermis forces water entering via the apoplast pathway to switch to the symplast pathway. What is its function?
25. The movement of water from the soil into the root xylem can occur via the symplast and apoplast pathways. Which pathway involves movement through the cytoplasm of cells?
26. Which of the following structures in the root is primarily responsible for water absorption from the soil?
27. The potential difference that drives water movement across a semipermeable membrane is the difference in:
28. Plasmolysis occurs when a plant cell is placed in a solution that is:
29. A plant cell with a negative solute potential and a positive pressure potential indicates:
30. Adding a solute to pure water will cause the solute potential (Ψs) to become:
31. The water potential of pure water at standard temperature and pressure is defined as:
32. Guttation is the loss of water in liquid form from plant parts, often seen as droplets on leaf margins. It occurs when:
33. The upward movement of water in the xylem is a process of:
34. Root pressure can contribute to the ascent of sap, especially under conditions of:
35. What is the role of tension in the ascent of sap according to the Cohesion-Tension Theory?
36. Adhesion, in the context of water transport in plants, refers to the attraction between water molecules and:
37. Cohesion refers to the attraction between water molecules due to:
38. The 'Cohesion-Tension Theory' explains the mechanism of:
39. When stomata close, transpiration rate decreases, but this also affects:
40. Which of the following factors does NOT significantly affect the rate of transpiration?
41. The primary driving force for transpiration is:
42. Stomata are pores that regulate gas exchange and transpiration. They are typically found on:
43. Which term describes the outward movement of water in liquid form from plant surfaces, mainly through stomata?
44. The process by which water moves into a plant root from the soil is primarily driven by:
45. If a plant cell is placed in a hypertonic solution, water will move:
46. What is the term for the pressure exerted by the cell wall against the protoplast of a plant cell?
47. Water moves from a region of higher water potential to a region of lower water potential. This statement describes:
48. In a turgid plant cell, which component of water potential is significantly positive?
49. Which component of water potential is always zero or negative in a plant cell?
50. What is the symbol commonly used to represent water potential?