eumelanin的用法和樣例：
例句
- Phaeomelanin is responsible for the yellowish-blond to red colors and Eumelanin is responsible for the brown to black shades.
棕黑素形成亞麻色到紅色發質，真黑素形成棕色到黑色。 - Both animals and humans have phenotypic variations of eye color that are attributed to ratios of eumelanin, a substance produced by melanocytic cells in the iris.
動物和人都有眼睛顏色的表徵變化，這是由於真黑素含量不同造成的，真黑素是虹膜中的黑色素細胞產生的一種物質。
