Final answer:
Root hairs are tubular extensions of epidermal cells in plants' roots that increase the absorptive surface area. They help in the absorption of water and minerals from the soil.
Step-by-step explanation:
Plants can increase the absorptive surface area of their roots by making root hairs.
The root hairs are tubular extensions of epidermal cells.
The epidermis is the outer layer of cells in the root that surrounds areas of ground tissue and vascular tissue.
The thin-walled epidermal cells and root hairs greatly contribute to the absorption of water and minerals from the soil.