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.
Varicose veins are veins that have become enlarged and twisted. The term commonly refers to the veins on the leg, although varicose veins can occur elsewhere. Veins have pairs of leaflet valves to prevent blood from flowing backwards (retrograde flow or venous reflux).Leg muscles pump the veins to return blood to the heart (the skeletal-muscle pump), against the effects of gravity.hen veins become varicose, the leaflets of the valves no longer meet properly, and the valves do not work (valvular incompetence). This allows blood to flow backwards and they enlarge even more. Varicose veins are most common in the superficial veins of the legs, which are subject to high pressure when standing.