鳘鱼和鳕鱼等几种鱼类的肝脏,向来被认为维他命A 的主要来源,植物只不过供给维他命A的化学的母体.即胡萝卜素Carotene,那就是说维他命A 的本身乃因动物摄取了植物性食物后,才能在肝里边构成的。这个学说最近已被美国瓦萨大学的E.A.Roberts 教授的研究所推翻了。他们利用电子显微镜作工具,发见幼植物和蔬菜 The liver of several species of fish, such as catfish and cod, has long been recognized as the main source of vitamin A. Plants supply only chemical precursors of vitamin A. Carotene, which means that vitamin A itself is consumed by animals Sexual food, can be formed in the liver inside. This doctrine has recently been overthrown by the institute of Professor E.A. Roberts of the University of Vaasa. They use electron microscopy as a tool to see young plants and vegetables