Explain why xylem transport is unidirectional and phloem transport bi-directional.
Explain why xylem transport is unidirectional and phloem transport bi-directional.

Solution: When water is absorbed by roots through the xylem, it only travels upward. As a result, water transport is one-way. The phloem tissue transports the food. Food is created in the leaves and is required by both the roots and the shoot system, thus phloem sap travels both upwards and downwards, making food transport bidirectional and allowing it to reach other plant sections.