Q. Identify true and false statements and select the correct option from the codes given below I. As suction pressure increases, water absorption also increases which in turn increases the absorption of ions II. Absorption of ions is affected by transpiration pull III. Large amount of charged particles are absorbed along with absorption of water IV. Pressure flow hypothesis depends entirely on the existence of mechanism for loading sugars into phloem at the source region and unloading it at the sink V. Contents in the sieve tube move undirectionally
A) I, II, III and IV are true while V as false
B) I, III, IV and are true while II is false
C) I, II, IV and V are true while III is false
D) II, III, IV and V are true while I is false
Explanation
Suction pressure or transpiration pull is a tension caused by transpiration from the surface of leaves in a plant. This tension or pull creates a tension in the water column of xylem, which in turn absorbs water from the soil along with minerals. Absorption of ions or minerals is affected by transpirational pull. Pressure flow hypothesis or Munch flow hypothesis depends completely on the existence of mechanism for loading organic nutrients (sugars) into sieve tube phloem and deliver the same to the site of utilisation. Source sink relationship is variable
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.