What is the primary function of xylem in trees?

• A. Transports water and minerals from the roots to the leaves and provides structural support.
• B. Transports sugars and other organic nutrients from sources to sinks.
• C. Stores carbohydrates as starch in the trunk.
• D. Absorbs nutrients from the air.

Answer: (A)

Xylem’s main job is to move water and minerals from the roots up to the leaves, which is essential for photosynthesis and nutrient delivery. The water is pulled upward by transpiration in the leaves, with cohesion and adhesion helping to keep a continuous column through the xylem vessels and tracheids. In addition to transport, xylem fibers have thick, lignified walls that give the plant its structural support, helping the tree stand upright and grow tall. The other functions listed belong to different tissues: phloem transports sugars and other organic nutrients, stored carbohydrates are found in storage tissues like parenchyma, and nutrient absorption from the air isn’t a function of xylem.