leucobase

例句：

1. 1. The leucobase in the blood is responsible for the color of your skin.
   血液中的酪氨酸基团负责你皮肤的颜色。
2. 2. The leucobase in urine is a good indicator of kidney function.
   尿液中的酪氨酸基团是肾脏功能的一个良好指标。
3. 3. The leucobase in hair is used to determine age and health.
   头发中的酪氨酸基团用于确定年龄和健康状况。