vascular tissue

This term is a technical biological designation used primarily in botany and anatomy. It describes the structural network responsible for long-distance transport, distinguishing complex plants from simpler organisms like mosses that lack such a system.

Because it refers to a biological system or a type of material, it is treated as an uncountable noun. It is not referred to in the plural as "vascular tissues" when discussing the general physiological system, though it may be used in the plural when referring to different types of tissues across various species.