alleryThe unbroken water column in xylem stays joined chiefly because of
AFriction inside the xylem walls
BCohesion between water molecules
CActive pumping by phloem cells
DPressure of soil air in the pores
Answer & Solution
Correct answer: B. Cohesion between water molecules
1. Water molecules attract each other by hydrogen bonding.
2. This mutual attraction is called cohesion.
3. Cohesion keeps the xylem column unbroken under transpiration pull.
4. Hence cohesion is the holding force.
_Source: Selina Concise Biology Class 8, Ch on Transport in Plants (Mistral OCR'd PDF), Ascent of Sap_
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