1. _________holds water together and forms a chain like column in xylem tubes
A. Cohesion
B. Tension
C. Adhesion
D. Root pressure
2. Xylem water tension can pull water up to ______ at it's maximum
A. 25meter
B. 50 meter
C. 100 meter
D. 200 meter
3. The ______component of cell wall has great affinity for water.
A. Cellulose
B. Pectin
C. Lignin
D. Starch
4. In tall trees speed of water carried upward is up to
A. 1 meter per hour
B. 2 meter per hour
C. 4 meter per hour
D. 8 meter per hour
5. As a leaf transpires the water potential of its mesophyll cells
A. Rise
B. Drop
C. Remain same
D. Increase rapidly
6. ______ is created by active secretion of salts from other cells into xylem sap.
A. Cohesion
B. Tension
C. Adhesion
D. Root pressure
7. Water which enters xylem cells may take _____pathway to move upwards.
A. Apoplast
B. Symplast
C. Vacuolar
D. All
8. The dew drops seen on tips of strawberry leaves or grass are due to
A. Rainfall
B. Frost
C. Guttation
D. Respiration
9. Guttation is more when transpiration is _______and relative humidity is _____
A. Sufficient, high
B. Suppressed, high
C. Sufficient, low
D. Suppressed, low
10. Cohesion tension theory was proposed by ______and phenomenon of imbibition was suggested by _______
A. Dixon, sacks
B. Sacks, Dixon
C. Van mohl, Dixon
D. Van mohl, sacks
11. The_______ in cell wall can take up water without being dissolved and increase the volume
A. Cellulose
B. Pectin
C. Lignin
D. All
12. The water imbibed by root cell wall from soil moves by
A. Apoplast pathway
B. Symplast pathway
C. Vacuolar pathway
D. C3 pathway
13. Imbibition is ______process and it is especially important in
A. Reversible, germinating seed
B. Irreversible, germinating seed
C. Reversible, photosynthesizing leaf
D. Irreversible, photosynthesizing leaf
14. Imbibition may increase volume of dry seed up to
A. 200 times
B. 250 times
C. 300 times
D. 350 times
15. Bleeding often seen in
A. Palms
B. Grape wine
C. Sugar maple
D. All
16. Which of the following is responsible for bleeding in plant
A. Hydrostatic pressure in xylem
B. Hydrostatic pressure in phloem elements
C. Root pressure exerted by xylem tissues of roots
D. All
17. Depending upon the path of escape of water vapours from aerial parts of plant transpiration has ____ types
A. 2
B. 3
C. 4
D. 5
18. Cuticular transpiration is about _____of total transpiration
A. 1-2%
B. 5-7%
C. 50%
D. 90%
19. Lenticular transpiration is about ____of total transpiration
A. 1-2%
B. 5-7%
C. 50%
D. 90%
20. _____ are aerating pores form in bark through which transpiration occurs
A. Hydathodes
B. Lenticels
C. Stomatal pores
D. Guttation