Root

A root was the part of a plant used to derive nourishment.

The Vurosis' main body was composed of a system of interlocking white roots. Though they grew haphazardly, they could later be grown in specific patterns and organisations. Many of these roots had black eyes. These roots were warm to the touch and glowed green in the dark. (PROSE: Wishing Well)

Krynoids required animal proteins while young, but could survive on normal photosynthesis later in life, and gathered nitrogen directly from the air without a need for roots. (TV: The Seeds of Doom)

Captain Rostrum was an artificial plant lifeform that served as captain and crew of the EBV Nevermore. Its form was a mass of trunks with roots, tendrils, leaves, and seed pods. (AUDIO: Here There Be Monsters)