For example, a peripheral neuropathy caused by a vitamin deficiency can be treated -- even reversed -- with vitamin therapy and an improved diet. Likewise, nerve damage brought on by alcohol abuse can often be stopped and improved by avoiding alcohol.
2. Vascular tissue - xylem and phloem in leaves form in strands called veins. Xylem forms on the upper side of a vein (on a vertical leaf, on the side next to the stem), and phloem on the lower side (side away from the stem). a. Veins are like a leaf's fingerprint and can be used to identify plants.
Groups of capillaries within a tissue reunite to form small veins called venules. Venules collect blood from capillaries and drain into veins. Veins are the blood vessels that carry blood back to the heart. They may contain valves which stop blood flowing away from the heart.