ISA Certified Arborist Practice Exam

The vascular tissue responsible for transporting water in trees is xylem. Xylem is a type of vascular tissue that plays a crucial role in the movement of water and dissolved minerals from the roots of the tree to the leaves and other parts of the plant. This transport process is essential for maintaining hydration and supporting photosynthesis, which occurs primarily in the leaves.

Xylem consists of various specialized cells, including tracheids and vessel elements, which facilitate the flow of water through capillary action and transpiration pull. The structure of xylem allows it to withstand the pressure created by the movement of water, making it effective in sustaining the tree's height and overall health.

In contrast, phloem is the vascular tissue responsible for transporting nutrients and sugars produced during photosynthesis from the leaves to other parts of the plant. Cambium is a layer of tissue that contributes to the growth of the plant by generating new xylem and phloem cells, while "derivates" could refer to various derived plant tissues but does not specifically denote any vascular transport function. Thus, xylem is the definitive answer regarding water transport in trees.