orthotropous

形容词 orthotropous:

1. (of a plant ovule) completely straight with the micropyle at the apex

or.thot.ro.pous

adj.Botany （形容词）【植物学】
Growing straight, so that the micropyle is at the end opposite the stalk. Used of an ovule.
直生的：直立生长以至珠孔在茎的另一端的。用于形容胚珠