Plants are classified based on the presence of a certain specialized tissue. A specialized tissue called vascular tissue which helps transport nutrients and water to all parts of the plant.
Explanation;
Vascular tissue is a conducting tissue that is formed by more than one cell type which is found in vascular plants.
Plants may be classified as vascular plants or non-vascular plants depending on whether they have or lack vascular tissues.
Vascular tissue is mainly made up of the xylem and the phloem, whose main role is transport of fluids and nutrients in vascular plants.
Xylem conducts water and mineral salts from the roots upward and through out the plant, while the phloem transports dissolved nutrients to all parts of the plants.