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.
The leaves of plants also contain veins, through which nutrients and hormones travel to reach the cells throughout the leaf. Veins are easy to see some leaves (a maple tree, for instance). In some plants the veins are hard to see, but theyâre in there. Sap is the mix of water and minerals that move through the xylem.