Movement of fluids in plants from base to tip occurs through which tissue?

• A. Xylem
• B. Phloem
• C. Residue
• D. Tiller

Answer: (A)

Water moves upward from the roots through the xylem. Xylem is made of hollow, dead cells with thick, lignified walls that form continuous tubes from roots to leaves, so it can transport water and minerals throughout the plant. The main force driving this upward movement is transpiration at the leaves: as water evaporates from leaf surfaces, a negative pressure (tension) is created that pulls more water upward through the xylem. Cohesion between water molecules helps keep the column intact, and adhesion to the xylem walls helps resist gravity. Root pressure can contribute a bit, but it’s not the main driver for long-distance upward movement. Phloem, in contrast, carries organic nutrients like sugars and can move them in various directions, not primarily as a bulk upward flow of water. Residue and tiller are not tissues involved in water transport.