Absorption by Roots - Complete Question Paper

Section A: Multiple Choice Questions (MCQ) - 100 Questions (1 mark each)

1. The phenomenon of absorption of water by solid particles without forming a solution is called: a) Diffusion b) Osmosis c) Imbibition d) Transpiration

2. When seeds swell after soaking in water, this process is an example of: a) Osmosis b) Imbibition c) Diffusion d) Active transport

3. The net movement of molecules from higher concentration to lower concentration is: a) Osmosis b) Imbibition c) Diffusion d) Plasmolysis

4. Osmosis is the movement of: a) Solute molecules b) Solvent molecules c) Both solute and solvent d) None of these

5. A selectively permeable membrane allows: a) All molecules to pass b) Only solvent molecules c) Only solute molecules d) No molecules

6. The minimum pressure needed to prevent osmosis is called: a) Root pressure b) Osmotic pressure c) Turgor pressure d) Atmospheric pressure

7. Root pressure is responsible for: a) Water absorption b) Sap rising in stem c) Transpiration d) Photosynthesis

8. Turgidity in plant cells is caused by: a) Water loss b) Water absorption c) Solute accumulation d) Cell division

9. When plant cells lose water in hypertonic solution, the process is called: a) Turgidity b) Plasmolysis c) Flaccidity d) Imbibition

10. The condition where plasma membrane is not pressed against cell wall is: a) Turgidity b) Plasmolysis c) Flaccidity d) Osmosis

11. Active transport requires: a) Energy b) Concentration gradient c) Passive movement d) All of these

12. Passive transport occurs: a) Against concentration gradient b) Along concentration gradient c) With energy input d) Through active sites

13. The upward movement of water from roots to aerial parts is called: a) Root pressure b) Osmotic pressure c) Ascent of sap d) Transpiration

14. Cohesion refers to: a) Attraction between unlike molecules b) Attraction between like molecules c) Repulsion between molecules d) None of these

15. Adhesion is the tendency of: a) Like molecules to stick together b) Unlike molecules to stick together c) Molecules to repel d) Water to evaporate

16. Transpiration pull is responsible for: a) Water absorption b) Water transport upward c) Photosynthesis d) Respiration

17. Which process does not require a membrane? a) Osmosis b) Active transport c) Diffusion d) None of these

18. Root hairs increase: a) Root length b) Root strength c) Surface area d) Root pressure

19. The driving force for osmosis is: a) Temperature difference b) Pressure difference c) Concentration difference d) pH difference

20. In a hypotonic solution, plant cells become: a) Flaccid b) Plasmolyzed c) Turgid d) Shrunken

21. Water potential is highest in: a) Pure water b) Concentrated solution c) Hypertonic solution d) Isotonic solution

22. The term isotonic means: a) Same concentration b) Different concentration c) Higher concentration d) Lower concentration

23. Endosmosis occurs when: a) Water moves out of cell b) Water moves into cell c) Solutes move out d) No movement occurs

24. Exosmosis results in: a) Cell swelling b) Cell shrinking c) No change d) Cell bursting

25. The cell wall of plant cells is: a) Fully permeable b) Semi-permeable c) Impermeable d) Selectively permeable

26. Turgor pressure helps in: a) Cell support b) Growth c) Opening of stomata d) All of these

27. The loss of turgor pressure leads to: a) Wilting b) Growth c) Photosynthesis d) Respiration

28. Water moves from soil to root through: a) Active transport only b) Passive transport only c) Both active and passive d) Neither

29. The concentration of solutes is highest in: a) Soil water b) Root cells c) Xylem d) Varies with plant

30. Symplastic pathway involves movement through: a) Cell walls b) Intercellular spaces c) Cytoplasm d) Xylem vessels

31. Apoplastic pathway involves movement through: a) Cytoplasm b) Cell walls c) Vacuoles d) Nucleus

32. The Casparian strip is found in: a) Epidermis b) Cortex c) Endodermis d) Pericycle

33. Water absorption is maximum during: a) Day time b) Night time c) Evening d) Constant throughout

34. The main driving force for water absorption is: a) Root pressure b) Transpiration pull c) Osmotic pressure d) All contribute

35. Guttation occurs due to: a) Transpiration b) Root pressure c) Osmosis d) Diffusion

36. Hydathodes are involved in: a) Transpiration b) Guttation c) Absorption d) Photosynthesis

37. The rate of transpiration is affected by: a) Temperature b) Humidity c) Wind speed d) All of these

38. Stomata are mainly present on: a) Upper surface b) Lower surface c) Both surfaces d) Stem only

39. Guard cells control: a) Photosynthesis b) Respiration c) Transpiration d) Absorption

40. The opening and closing of stomata depends on: a) Light b) CO2 concentration c) Water availability d) All of these

41. C4 plants have: a) Higher water use efficiency b) Lower water use efficiency c) Same as C3 plants d) No transpiration

42. Xerophytes are adapted to: a) High water availability b) Low water availability c) Moderate water d) Aquatic conditions

43. Hydrophytes are adapted to: a) Dry conditions b) Aquatic conditions c) Desert conditions d) Mountain conditions

44. Mesophytes grow in: a) Very dry conditions b) Very wet conditions c) Moderate conditions d) Extreme conditions

45. CAM plants open stomata during: a) Day time b) Night time c) Morning d) Evening

46. The waxy coating on leaves is called: a) Cuticle b) Epidermis c) Mesophyll d) Stomata

47. Succulent plants store water in: a) Roots b) Stems c) Leaves d) All of these

48. Wilting occurs when: a) Water absorption > Water loss b) Water absorption < Water loss c) Water absorption = Water loss d) No water absorption

49. Temporary wilting is due to: a) Soil water shortage b) High transpiration rate c) Disease d) Old age

50. Permanent wilting occurs when: a) Soil has no water b) Plant is diseased c) Transpiration is high d) Roots are damaged

51. The water potential of pure water is: a) Zero b) Positive c) Negative d) Infinite

52. Solute potential is always: a) Positive b) Negative c) Zero d) Variable

53. Pressure potential in turgid cells is: a) Positive b) Negative c) Zero d) Infinite

54. Water always moves from: a) Lower to higher water potential b) Higher to lower water potential c) Equal water potentials d) No specific direction

55. The unit of water potential is: a) Pascal b) Atmosphere c) Bar d) All of these

56. Plasmolysis can be reversed by placing cells in: a) Hypertonic solution b) Hypotonic solution c) Isotonic solution d) Pure water

57. Incipient plasmolysis occurs when: a) Cell membrane just separates from cell wall b) Cell is fully plasmolyzed c) Cell is turgid d) Cell is flaccid

58. The point at which plasmolysis just begins is: a) Incipient plasmolysis b) Complete plasmolysis c) Partial plasmolysis d) No plasmolysis

59. Deplasmolysis occurs when: a) Plasmolyzed cells regain water b) Turgid cells lose water c) Cells divide d) Cells die

60. Cytorrhysis is: a) Reversible plasmolysis b) Irreversible plasmolysis c) Deplasmolysis d) Turgidity

61. The term 'semipermeable membrane' was coined by: a) Traube b) Pfeffer c) De Vries d) Dutrochet

62. The first demonstration of osmosis was by: a) Traube b) Pfeffer c) Dutrochet d) De Vries

63. Osmotic pressure was first measured by: a) Traube b) Pfeffer c) Dutrochet d) De Vries

64. The study of plasmolysis was pioneered by: a) Traube b) Pfeffer c) De Vries d) Dutrochet

65. Imbibition was first studied in detail by: a) Sachs b) Reinke c) Rodewald d) All of these

66. The swelling pressure developed during imbibition can be: a) Very low b) Moderate c) Very high d) Zero

67. Imbibition is affected by: a) Temperature b) pH c) Nature of imbibant d) All of these

68. Dry seeds can imbibe water up to: a) 10-20% of their weight b) 50-100% of their weight c) 200-300% of their weight d) 1000% of their weight

69. The rate of imbibition is highest in: a) Beginning b) Middle phase c) End phase d) Constant throughout

70. Imbibition causes: a) Increase in volume b) Decrease in volume c) No change in volume d) Variable changes

71. The force responsible for ascent of sap is: a) Root pressure only b) Transpiration pull only c) Both root pressure and transpiration pull d) Osmotic pressure only

72. Cohesion-tension theory was proposed by: a) Dixon and Joly b) Godlewski c) Priestley d) Bose

73. The diameter of xylem vessels affects: a) Cohesion b) Adhesion c) Transpiration pull d) All of these

74. Cavitation in xylem occurs due to: a) High tension b) Low tension c) No tension d) Moderate tension

75. Air bubbles in xylem are called: a) Cavitation b) Embolism c) Emboli d) All of these

76. The maximum height water can rise due to capillarity alone is: a) 1-2 meters b) 10-20 meters c) 50-100 meters d) 200-300 meters

77. Root pressure can raise water up to: a) Few centimeters b) Few meters c) 10-20 meters d) 100 meters

78. Bleeding in plants is due to: a) Transpiration b) Root pressure c) Osmosis d) Diffusion

79. The tallest trees rely mainly on: a) Root pressure b) Transpiration pull c) Capillarity d) Osmotic pressure

80. Water movement in xylem is: a) Unidirectional upward b) Bidirectional c) Downward only d) Random

81. The conducting elements of xylem are: a) Vessels and tracheids b) Sieve tubes c) Companion cells d) Parenchyma

82. Tracheids are found in: a) Angiosperms only b) Gymnosperms only c) Both angiosperms and gymnosperms d) Neither

83. Vessels are characteristic of: a) Angiosperms b) Gymnosperms c) Pteridophytes d) Bryophytes

84. The end walls of vessels have: a) Simple pits b) Bordered pits c) Perforation plates d) No openings

85. Bordered pits are mainly found in: a) Vessels b) Tracheids c) Sieve tubes d) Parenchyma

86. The secondary wall thickenings in tracheids are: a) Spiral b) Annular c) Reticulate d) All of these

87. Lignification makes xylem elements: a) Living b) Dead c) Semi-living d) Variable

88. Water conduction in xylem is through: a) Living cells b) Dead cells c) Both d) Neither

89. The most efficient water conducting elements are: a) Tracheids b) Vessels c) Sieve tubes d) Parenchyma

90. Tyloses formation occurs in: a) Young xylem b) Old xylem c) Phloem d) Cambium

91. Heartwood is: a) Functional b) Non-functional c) Partially functional d) Variable

92. Sapwood is the: a) Outer functional wood b) Inner non-functional wood c) Cambium d) Phloem

93. Annual rings in wood represent: a) Age of tree b) Seasonal variations c) Environmental conditions d) All of these

94. Early wood has: a) Large vessels b) Small vessels c) No vessels d) Thick walls

95. Late wood is characterized by: a) Large vessels b) Small vessels c) Thin walls d) More parenchyma

96. Ring-porous wood has: a) Vessels uniformly distributed b) Large vessels in early wood c) Small vessels throughout d) No vessels

97. Diffuse-porous wood has: a) Vessels uniformly distributed b) Large vessels in early wood c) No vessels d) Vessels only in late wood

98. Reaction wood is formed in response to: a) Gravity b) Light c) Water d) Nutrients

99. Compression wood is found in: a) Angiosperms b) Gymnosperms c) Both d) Neither

100. Tension wood is characteristic of: a) Angiosperms b) Gymnosperms c) Both d) Neither

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Section B: Short Answer Questions (1 mark each) - 100 Questions

1. Define imbibition.

2. What is diffusion?

3. Define osmosis.

4. What is osmotic pressure?

5. Define root pressure.

6. What is turgidity?

7. Define plasmolysis.

8. What is flaccidity?

9. Define active transport.

10. What is passive transport?

11. Define ascent of sap.

12. What is cohesion?

13. Define adhesion.

14. What is transpiration pull?

15. Name the process by which seeds swell in water.

16. What type of transport requires energy?

17. In which direction does diffusion occur?

18. What is a selectively permeable membrane?

19. Name the pressure that prevents osmosis.

20. What causes sap to rise in plant stems?

21. What happens to cells in hypertonic solution?

22. What is the condition when plasma membrane detaches from cell wall?

23. Which transport process works against concentration gradient?

24. What is the upward movement of water in plants called?

25. Define water potential.

26. What is solute potential?

27. Define pressure potential.

28. What is turgor pressure?

29. Name the pathway through cell walls.

30. What is symplastic pathway?

31. Where is the Casparian strip located?

32. What is guttation?

33. Define hydathodes.

34. What controls stomatal opening?

35. Name plants adapted to dry conditions.

36. What are hydrophytes?

37. Define mesophytes.

38. When do CAM plants open stomata?

39. What is the waxy layer on leaves called?

40. Define wilting.

41. What is temporary wilting?

42. Define permanent wilting point.

43. What is incipient plasmolysis?

44. Define deplasmolysis.

45. What is cytorrhysis?

46. Name the theory explaining ascent of sap.

47. What is cavitation?

48. Define embolism in plants.

49. What is bleeding in plants?

50. Name the conducting elements of xylem.

51. What are tracheids?

52. Define vessels.

53. What are perforation plates?

54. What are bordered pits?

55. What is lignification?

56. Define tyloses.

57. What is heartwood?

58. Define sapwood.

59. What are annual rings?

60. Define early wood.

61. What is late wood?

62. Define ring-porous wood.

63. What is diffuse-porous wood?

64. Define reaction wood.

65. What is compression wood?

66. Define tension wood.

67. What is endosmosis?

68. Define exosmosis.

69. What is isotonic solution?

70. Define hypertonic solution.

71. What is hypotonic solution?

72. Define water use efficiency.

73. What are succulents?

74. Define xeromorphic adaptations.

75. What is the cuticle?

76. Define stomatal frequency.

77. What is transpiration ratio?

78. Define water deficit.

79. What is water stress?

80. Define drought resistance.

81. What is osmotic adjustment?

82. Define compatible solutes.

83. What is hydraulic conductivity?

84. Define xylem pressure potential.

85. What is the apoplast?

86. Define symplast.

87. What is the transmembrane pathway?

88. Define bulk flow.

89. What is mass flow?

90. Define hydraulic redistribution.

91. What is root hydraulic conductance?

92. Define aquaporins.

93. What is the endodermis?

94. Define the pericycle.

95. What is the cortex in roots?

96. Define root cap.

97. What are root hairs?

98. Define the zone of elongation.

99. What is the meristematic zone?

100. Define the zone of maturation.

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Section C: Short Answer Questions (2 marks each) - 100 Questions

1. Explain the process of imbibition with an example.

2. Distinguish between diffusion and osmosis.

3. Describe the factors affecting osmotic pressure.

4. Explain how root pressure is generated.

5. Compare turgid and flaccid conditions in plant cells.

6. Describe the process of plasmolysis.

7. Differentiate between active and passive transport.

8. Explain the mechanism of ascent of sap.

9. Describe the role of cohesion and adhesion in water transport.

10. Explain the transpiration pull theory.

11. Describe the structure and function of root hairs.

12. Explain the significance of water potential in plants.

13. Describe the apoplastic and symplastic pathways.

14. Explain the role of Casparian strip in water absorption.

15. Describe the process of guttation.

16. Compare stomatal and cuticular transpiration.

17. Explain the adaptations of xerophytes.

18. Describe the characteristics of hydrophytes.

19. Explain CAM photosynthesis in relation to water conservation.

20. Describe the factors causing wilting in plants.

21. Explain temporary and permanent wilting.

22. Describe the demonstration of osmosis using a thistle funnel.

23. Explain the relationship between water potential and its components.

24. Describe the mechanism of stomatal movement.

25. Explain the role of guard cells in transpiration.

26. Describe the factors affecting rate of transpiration.

27. Explain the importance of transpiration in plants.

28. Describe the structure of xylem tissue.

29. Compare vessels and tracheids.

30. Explain the formation of annual rings.

31. Describe the difference between early wood and late wood.

32. Explain the concept of cavitation in xylem.

33. Describe the role of root pressure in guttation.

34. Explain the cohesion-tension theory.

35. Describe the limitations of root pressure theory.

36. Explain the experimental evidence for transpiration pull.

37. Describe the measurement of osmotic pressure.

38. Explain the significance of turgor pressure.

39. Describe the process of plasmolysis and deplasmolysis.

40. Explain the factors affecting imbibition.

41. Describe the role of temperature in water absorption.

42. Explain the effect of soil conditions on water uptake.

43. Describe the relationship between transpiration and photosynthesis.

44. Explain the water economy of plants.

45. Describe the mechanism of water movement in soil.

46. Explain the concept of water use efficiency.

47. Describe the adaptations of desert plants.

48. Explain the water relations in halophytes.

49. Describe the role of mycorrhizae in water absorption.

50. Explain the significance of root-shoot ratio.

51. Describe the measurement of water potential.

52. Explain the concept of osmotic adjustment.

53. Describe the role of ABA in water stress.

54. Explain the mechanism of aquaporin function.

55. Describe the types of aquaporins in plants.

56. Explain the regulation of aquaporin activity.

57. Describe the path of water from soil to atmosphere.

58. Explain the soil-plant-atmosphere continuum.

59. Describe the measurement of transpiration rate.

60. Explain the diurnal variation in water absorption.

61. Describe the seasonal changes in water relations.

62. Explain the effect of environmental factors on water uptake.

63. Describe the role of calcium in water transport.

64. Explain the mechanism of ion uptake by roots.

65. Describe the coupling of water and solute transport.

66. Explain the concept of hydraulic lift.

67. Describe the embolism repair mechanisms.

68. Explain the vulnerability of xylem to cavitation.

69. Describe the safety-efficiency tradeoff in xylem.

70. Explain the role of pit membranes in water transport.

71. Describe the bordered pit structure and function.

72. Explain the difference between hardwood and softwood.

73. Describe the formation of reaction wood.

74. Explain the ecological significance of wood anatomy.

75. Describe the methods of measuring xylem pressure.

76. Explain the pressure probe technique.

77. Describe the psychrometer method for water potential.

78. Explain the thermocouple psychrometer.

79. Describe the pressure chamber technique.

80. Explain the measurement of hydraulic conductivity.

81. Describe the dye movement experiments.

82. Explain the isotope tracer studies in water transport.

83. Describe the use of MRI in studying water movement.

84. Explain the cryo-SEM studies of xylem.

85. Describe the mathematical models of water transport.

86. Explain the finite element modeling of xylem.

87. Describe the network models of xylem transport.

88. Explain the vulnerability curves of xylem.

89. Describe the acoustic detection of cavitation.

90. Explain the optical detection of emboli.

91. Describe the refilling of embolized vessels.

92. Explain the root pressure refilling mechanism.

93. Describe the seasonal patterns of embolism.

94. Explain the evolutionary aspects of xylem structure.

95. Describe the phylogenetic trends in vessel evolution.

96. Explain the developmental regulation of xylem.

97. Describe the hormonal control of xylem differentiation.

98. Explain the genetic basis of xylem formation.

99. Describe the biotechnological applications of water transport.

100. Explain the climate change impacts on plant water relations.

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Section D: Long Answer Questions (3 marks each) - 50 Questions

1. Describe the process of water absorption by roots, including the pathways involved and the driving forces.

2. Explain the cohesion-tension theory of ascent of sap. Include experimental evidence and limitations of this theory.

3. Describe the structure and function of xylem tissue. How does its anatomy relate to its function in water transport?

4. Explain the process of transpiration, its significance, and the factors that regulate it in plants.

5. Describe the various adaptations shown by xerophytic plants to conserve water. Give specific examples.

6. Explain the concept of water potential and its components. How does water potential gradient drive water movement in plants?

7. Describe the mechanism of stomatal movement. How do environmental factors influence stomatal behavior?

8. Explain the phenomenon of plasmolysis and its significance in understanding plant cell water relations.

9. Describe the different types of water transport pathways in plants from root to leaf. Compare their efficiency and regulation.

10. Explain the role of root pressure in water transport. How does it differ from transpiration pull?

11. Describe the experimental methods used to study water transport in plants. Include both classical and modern techniques.

12. Explain the relationship between plant water status and various physiological processes like photosynthesis and growth.

13. Describe the anatomical and physiological adaptations of hydrophytes. How do these plants manage excess water?

14. Explain the concept of embolism in xylem and the mechanisms plants use to repair embolized vessels.

15. Describe the seasonal variations in plant water relations and how plants cope with changing water availability.

16. Explain the soil-plant-atmosphere continuum and the factors that influence water movement along this pathway.

17. Describe the role of aquaporins in plant water transport. How is their activity regulated?

18. Explain the measurement techniques for determining plant water status and their applications in research.

19. Describe the evolutionary aspects of water transport systems in plants. How has xylem anatomy evolved?

20. Explain the impact of environmental stress on plant water relations and the adaptive responses.

21. Describe the mathematical modeling approaches used to understand water transport in plants.

22. Explain the relationship between xylem structure and vulnerability to drought stress.

23. Describe the mechanism of ion transport in relation to water uptake by roots.

24. Explain the diurnal and seasonal patterns of water movement in plants and their ecological significance.

25. Describe the biotechnological applications of understanding plant water relations in crop improvement.

26. Explain the comparative water relations between C3, C4, and CAM plants.

27. Describe the hydraulic architecture of plants and its optimization for water transport efficiency.

28. Explain the molecular mechanisms underlying drought tolerance in plants.

29. Describe the interaction between water transport and plant hormones, particularly ABA.

30. Explain the climate change impacts on plant water relations and potential adaptations.

31. Describe the cavitation resistance mechanisms in different plant species.

32. Explain the trade-offs between water transport efficiency and safety in xylem design.

33. Describe the role of mycorrhizal associations in plant water uptake and drought tolerance.

34. Explain the water relations in epiphytic plants and their specialized adaptations.

35. Describe the phenomenon of hydraulic redistribution and its ecological implications.

36. Explain the osmoregulation mechanisms in halophytic plants.

37. Describe the developmental regulation of xylem differentiation and its hormonal control.

38. Explain the genetic basis of drought tolerance and water use efficiency in crops.

39. Describe the physiological basis of irrigation scheduling in agriculture.

40. Explain the water relations in succulent plants and their water storage strategies.

41. Describe the comparative anatomy of wood in relation to climate and habitat.

42. Explain the acoustic and optical methods for detecting xylem dysfunction.

43. Describe the cellular mechanisms of osmotic adjustment in drought-stressed plants.

44. Explain the water relations in parasitic plants and their host interactions.

45. Describe the hydrodynamics of water flow in plant vascular systems.

46. Explain the coordination between water transport and carbon assimilation in plants.

47. Describe the water relations in carnivorous plants and their specialized adaptations.

48. Explain the biomechanics of water transport and its relationship to plant structure.

49. Describe the ecological water relations and plant community dynamics.

50. Explain the future prospects and challenges in plant water relations research.

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