胚芽鞘

例句：

1. 1. The plant'sbud is protected by a protective layerof cells called a cotyledon.
   植物的芽被一层称为胚芽鞘的保护细胞所保护。
2. 2. Theroots of the plant areprotected by a protective layer ofcells called a cotyledon.
   植物的根被一层称为胚芽鞘的保护细胞所保护。
3. 3. Thecotyledons areessential for the plant to absorbwater and nutrients from the soil.
   胚芽鞘对于植物从土壤中吸收水分和养分至关重要。