Certified Arborist Practice Exam

Water and dissolved essential minerals are transported within the tree in this tissue:

1. Xylem

2. Phloem

3. Photosynthesis

4. Transpiration

The correct answer is: Xylem

The correct choice is xylem, which is a specialized tissue in vascular plants responsible for the transport of water and dissolved minerals from the roots to the rest of the plant, including the leaves and stems. This upward movement of water and minerals is essential for various physiological processes, including photosynthesis, nutrient transport, and maintaining cell turgor pressure. Xylem consists of several types of cells, such as tracheids and vessel elements, which are designed to facilitate the rapid movement of water through the tree. The process is largely driven by transpiration, where water evaporates from the leaves, creating a negative pressure that pulls more water upward from the roots. In this context, other options like phloem, which primarily transports the products of photosynthesis (like sugars) from leaves to other parts of the plant, do not play a role in transporting water and minerals. Photosynthesis refers to the process by which plants convert light energy into chemical energy but does not pertain to transport tissue. Transpiration, while related to the movement of water, is the process of water vapor loss from plant surfaces rather than the actual transport of water within the tree structure. Therefore, xylem is the key tissue responsible for this function.