Some strains of S marcescens are capable of producing a pigment called prodigiosin, which ranges in color from dark red to pale pink, depending on the age of the colonies.
Vascular Tissue: the xylem and phloem in leaves are confined to vascular bundles or veins. Veins are surrounded by a layer of cells call the bundle sheath. The bundle sheath can be composed of parenchyma, colenchyma, or fibers.
This specialized cellular network is the vascular tissue system; plants with vascular tissues are referred to as vascular plants. The vascular tissue system is composed of two different types of tissues: xylem and phloem. Although both xylem and phloem form a continuous tissue system throughout the plant body, the two tissues have different functions. Xylem is the primary water- and mineral-conducting tissue, and phloem is the primary food-conducting tissue. Unlike the circulatory system in animals, the vascular tissue in plants does not recirculate water.