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 Circulatory System. Veins, arteries and capillaries are the three types of blood vessels in the circulatory system. The blood vessels carry blood, which contains antibodies, nutrients, oxygen, electrolytes and hormones, throughout the body to be used by the organs.eins. 1  Veins carry blood from throughout the body back to the heart. 2  The blood in the veins is dark red in color because it contains very little oxygen. 3  The walls of veins are not as strong as the walls of the arteries because they farther away from the heart, meaning they are subject to less pressure from the heart.