肾单位

例句：

1. 1. The kidneys filter waste products from the blood.
   肾脏过滤血液中的废物。
2. 2. The nephron is responsible for removing waste and excess substances from the blood.
   肾单位负责从血液中去除废物和多余物质。
3. 3. The glomerulus is where the blood first touches the kidneys.
   肾小球是血液首次与肾脏接触的地方。