Metabolic disorders arise from a variety of genetic defects involving chemical pathways within cells.代谢疾病的产生源自体内涉及化学通路的基因的缺陷。New pedestrian pathways are being built alongside the road.马路旁正在建新的人行道。We've had to bar visitors from the garden because some of the pathways aren't safe.我们不得不禁止游客进入花园，因为有些小路不太安全。