Protonema (pl. protonemata) The young bryophyte gametophyte that develops following spore germination.

苔藓中直接由孢子萌的结构称为原丝体。

Rhizoid A unicellular rootlike structure found in certain algae and in the gametophyte generation of the bryophytes and some ferns.

在一些藻、苔藓和裸子配子体中存在的由单个细胞的似根的结构。