1. Choose correct statement
A. Inner side of guard cells has thin cell wall
B. Outer convex side of guard cells has thick cell wall
C. In epidermis of leaf guard cells are only epidermal cells which are not connected by plasmodesmata
D. All
2. Stomatal transpiration is ________of total transpiration in plants
A. 1-2%
B. 5-7%
C. 50%
D. 90%
3. _______functions as multisensory hydraulic valves
A. Mesophyll cells
B. Phloem cells
C. Guard cells
D. Xylem cells
4. _______proposed that guard cells are only photosynthesizing cells of epidermis of leaf and during day time sugars are produced in them.
A. Dixon
B. Sacks
C. Van mohl
D. Mendel
5. ______is the pathway followed by water through leaf
A. Xylem-mesophyll Walls-air spaces-stomatal pore
B. Stomatal pore- mesophyll wall-air space-xylem
C. Xylem-stomatal pore-air spaces-mesophyll
D. Xylem-air spaces-mesophyll-stomatal pore
6. When sugar level rises in guard cells
A. Water potential decreases
B. Guard cells become turgid
C. Stoma opens
D. All
7. Choose correct statement
A. Low level of CO2 favours opening of stomata
B. Exposure to blue light causes opening of stomata
C. Due to rise in sugar level stoma opens
D. All
8. A hormone called_____is released by ______cells when leaf cells due to exposure to high temperatures starts wilting. This hormone stops active transport of K+ into guard cells
A. Abscisic acid, guard cells
B. Cytokinine, guard cells
C. Abscisic acid, mesophyll cells
D. Cytokinin, mesophyll cells
9. Phloem tissue contains
A. Sieve elements
B. Companion cells
C. Parenchyma cells
D. All
10. Only ______is involved directly in transport of organic solutes
A. Sieve elements
B. Companion cells
C. Parenchyma cells
D. Sclereids
11. Companion cells supply ______ to sieve tubes
A. Oxygen
B. ATP
C. Protein
D. Both B and C
12. Direction of Phloem transport
A. Is exclusively downward
B. Defined with respect of gravity
C. From source to sink
D. All are correct
13. Sinks are the areas of active metabolism _____may be a sink
A. Tubers
B. Developing fruits
C. Immature leaves
D. All
14. Phloem feeding Insects puncture ________to reach the sap
A. Fibers
B. Parenchyma cells
C. Sieve tubes
D. Companion cells
15. Honey dew contains 10-25% dry matter _____of which is sucrose and ______ are nitrogenous compounds.
A. 90%, 1%
B. 1%, 90%
C. 70%, 30%
D. 30%, 70%
16. _______is most acceptable for transport in phloem of angiosperms
A. Active theory
B. Diffusion theory
C. Pressure flow theory
D. Cohesion tension theory
17. Diffusion can move sugar in phloem with velocity of
A. 1 meter per 8 hours
B. 1 meter per 8 days
C. 1 meter per 8 weeks
D. 1 meter per 8 years
18. Pressure flow theory was proposed by
A. Dixon
B. Sacks
C. Van mohl
D. Ernst Munch
19. _______ creates turgor pressure in sieve elements which forces _______ down phloem tubes towards ________
A. Water, sucrose and fluids, sink
B. Sucrose, water, sink
C. Water, sucrose, source
D. Water, glucose, sink
20. ________pressure in the leaf end of phloem and _______pressure in fruit end cause flow of water and solutes from ______to __________
A. High,low,source,sink
B. Low, high, source, sink
C. High, low, sink, source
D. Low, high, sink, source