Q. Read the following statement carefully and choose the right answer from the codes given below I. PMA and silicon oil of low viscosity are considered as antitranspirant II. BAP, NAA and cobalt chloride is also used as antitranspirant III. Abscisic acid affects the mechanism of opening and closing of stomata IV. Starch of guard cells is converted into PEP ions by the process of hydrolysis V. Potometer works on the principle of potential difference between the tip of the tube and that of plant VI. Transpiration rate is directly proportional to the relative humidity
A) I, II, III, IV, V and VI
B) I, II, III and IV are correct while V and IV are incorrect
C) V and VI are correct, while, I, VI, III and IV are incorrect
D) I, III, VI are correct, while II, IV, V are correct
Explanation
Potometer is used to measure the rate of transpiration and it works on the principle that the amount of water absorbed is equals the amount of water transpired. Transpiration rate is inversely proportional to the relative humidity, i.e., rate to transpiration is lower in higher relative humidity while lower humidity (dry air) increases the rate of transpiration
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.