Stimulation of the sympathetic nervous system is required
The outer layer of the skin covering the exterior body surface<span> of vertebrates ... the primary tissue of higher plants composed of </span>thin<span>-walled </span>cells<span> that remain capable of ... a swelling on a plant stem consisting of overlapping immature </span>leaves<span> or petals ... Older xylem </span>near<span> the center of a woody stem that no longer conducts water.</span>
The cell grows,then separates,then prepares for mitosis
It is now a new chemical reaction and has different properties now.
