Final answer:
Roots need different methods to absorb water and ions due to their different properties. Water is absorbed through root hairs, while ions are absorbed by thin-walled epidermal cells and root hairs, as well as through a mycorrhizal relationship with fungi.
Step-by-step explanation:
Roots need to use different methods to absorb water and ions because water and ions have different properties and require different mechanisms for uptake. Roots absorb water through root hairs, which are extensions of root epidermal cells that increase the surface area of the root for efficient water absorption.
Water moves through the permeable cell walls of the root epidermis and diffuses into the root cortex. On the other hand, ions (nutrients) are absorbed by thin-walled epidermal cells, root hairs, and a mycorrhizal relationship with fungi. Root hairs are especially important for nutrient absorption.