Std. 11th and Std. 12th Biology Question Papers. Appropriate for Medical Entrance Exams.
Sr. No. |
Questions |
Answers |
1. | Root pressure is due to (HAR-PMT, MP-PMT) (a) active absorption (b) passive absorption (c) increased transpiration (d) increased photosynthesis |
Answer: (d) |
2. | Root pressure theory was proposed by ________. (a) Priestley (b) Stocking (c) Boehm (d) Dixon |
Answer: (a) |
3. | The maximum absorption of water by roots occurs in the (region) zone of (M.P. PMT 2001) (a) root cap (b) cell division (c) cell elongation (d) root hairs |
Answer: (d) |
4. | Of the processes which occur in leaves, the one which may lower their temperature (cooling effect) is (DPMT 86) (a) respiration (b) Photosynthesis (c) Transpiration (d) hydrolysis |
Answer: (c) |
5. | Water is absorbed from outside solution only when it is (AFMC) (a) saturated (b) isotonic (c) hypertonic (d) hypotonic |
Answer: (d) |
6. | Stomata of a plant open due to (CBSE) (a) influx of potassium ions (b) Efflux of potassium ions (c) Influx of hydrogen ions (d) Influx of calcium ions |
Answer: (a) |
7. | Stomata close in response to (a) hot dry weather (b) abscisic acid (c) cytokinin (d) both (a) and (b) |
Answer: (d) |
8. | Cohesion-tension theory is related to ________. (a) respiration (b) ascent of sap (c) transpiration (d) photosynthesis |
Answer: (b) |
9. | The maximum loss of water in transpiration is from (Hariyana PMT 2005) (a) Lenticels (b) Cuticle (c) Stomata (d) Hydothodes |
Answer: (c) |
10. | The following percentage of water absorbed by herbaceous plants is lost in transpiration (JIPMER 2002, MPPMT, CPMT) (a) 80 (b) 60 (c) 99 (d) 40 |
Answer: (c) |
11. | Stomata open when the guard cells posses (CPMT) (a) less K+ (b) more ABA (c) More K+ (d) All of the above |
Answer: (c) |
12. | Water lost through transpiration is (a) pure water (b) rich in organic solutes (c) rich in dissolved salts (d) all the above |
Answer: (a) |
13. | The water available for plants in soil is ________. (a) gravitational water (b) hygroscopic water (c) capillary water (d) chemically bound water |
Answer: (c) |
14. | About ______ percent of water absorbed by plants is lost by transpiration. (a) 55 (b) 97 (c) 85 (d) 75 |
Answer: (b) |
15. | The conditions under which transpiration would be most rapid? (CPMT 81, AMU 87, BHU 77, DPMT 84) (a) High humidity (b) Excess of water in soil (c) Low humidity, high temperature, guard cell are turgid (open) moist soil (d) Low velocity of wind |
Answer: (c) |
16. | Transpiration is helpful to plants in (AFMC, CPMT) (a) Cooling (b) loss of excess nutrients (c) upward conduction/ascent of sap (d) loss of excess water |
Answer: (c) |
17. | Chlorophyllous cells fewer in number, unique in shape with inner walls thicker are(EAMCET) (a) guard cells (b) passage cells (c) subsidiary cells (d) bulliform cells |
Answer: (a) |
18. | Water in plants is transported by which of the followings? (a) Cambium (b) phloem (c) epidermis (d) xylem |
Answer: (d) |
19. | The most widely accepted theory of water translocation in plants is ______. (a) Root pressure theory (b) Capillary theory (c) Cohesion theory (d) Water pump theory |
Answer: (c) |
20. | Which is produced during water stress that brings stomatal closure? (JIPMER, RPMT [2000], CBSE, AMU, MP-PMT, BHU) (a) Ethylene (b) Abscisic acid (c) Ferulic acid (d) Coumarin |
Answer: (B) |