buffer stem

例句：

1. 1. The tree's buffer stem is strong enough to support its weight.
   这棵树的缓冲茎足够强壮，能支撑其重量。
2. 2. The plant's buffer stem helps it survive in harsh environments.
   这种植物的缓冲茎有助于它在恶劣环境中生存。
3. 3.The scientist used a buffer stem to prevent the sample from contaminating the test tube.
   科学家使用缓冲茎来防止样本污染试管。