Zinc(锌)isoneofabout20elements(元素)necessaryforgoodhealth...
问题详情：Zinc(锌)isoneofabout20elements(元素)necessaryforgoodhealth.Itispresentinthebodyinaverysmallamount,butitmakesitpossibleforimportantchemicalactionstobecarriedoutincells.Scientistsarejustbeginnin...