Certified Arborist Practice Test

The tissue that primarily exists for storage and transport in trees is phloem. Phloem is a type of vascular tissue responsible for the transport of organic nutrients, particularly sugars produced through photosynthesis, from the leaves to other parts of the plant, including the roots and developing fruits.

In addition to its role in transport, phloem also has parenchyma cells that can serve as storage units, storing starches, oils, and other substances. This dual role of storage and transportation makes phloem vital for the tree's overall function and health.

The other types of tissue mentioned serve different purposes. Parenchyma cells also contribute to storage but are more versatile and not exclusively linked to transport. Collenchyma provides structural support and flexibility primarily to young growing shoots and leaves. Sclerenchyma offers rigidity and strength to parts of the plant but does not play a significant role in storage or transport. Therefore, phloem is the most accurate answer regarding the tissues involved specifically in the storage and transport functions within trees.