Vitamin amino acids. Most vitamins are not single molecules, but groups of related molecules called vitamers. For example, vitamin E consists of four tocopherols and four tocotrienols. The thirteen vitamins required by human metabolism are: vitamin A (retinols and carotenoids), vitamin B (thiamine), vitamin B (riboflavin), vitamin B (niacin), vitamin B (pantothenic acid), vitamin B (pyridoxine), vitamin B (biotin), vitamin B (folic acid or folate), vitamin B (cobalamins), vitamin C (ascorbic acid), vitamin D (calciferols), vitamin E (tocopherols and tocotrienols), and vitamin K (quinones). Vitamins have diverse biochemical functions. Some forms of vitamin A function as regulators of cell and tissue
LNER Thompson Class B2 1958: in October, the name "Royal Sovereign" was transferred to no. 61632, which then became the official Royal engine. None of them survived the scrapyard to be preserved. LNER Thompson Class B2 The London and North Eastern Railway (LNER) Thompson Class B2 was a class of 4-6-0 steam locomotive. It was introduced in 1945 as a two-cylinder rebuild (with diagram 100A boiler) of the three-cylinder LNER Class B17. Ten were rebuilt from Class B17 but no more were rebuilt because of the success of the LNER Thompson Class B1. The LNER renumbered its locomotive stock during the period that these