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1·Apical buds produce a growth hormone called auxin.

顶芽分泌出叫做生长素的生长类激素。

2·Root growth is mainly determined by cell division and subsequent elongation in the root apical area. Components regulating cell division in root meristematic cells are largely unknown.

根的生长主要取决于根尖区的细胞分裂和伸长，而调控根尖分生组织细胞分裂的成分很大程度上是未知的。