protonema [ˌproʊtə'ni:mə]

例句:

• Protonema ( pl . protonemata ) The young bryophyte gametophyte that develops following spore germination.
  苔藓植物中直接由孢子萌发形成的结构称为原丝体.
  
• The process and protonema growth to development of the gametophyte are illustrated and taken microphotographs.
  在光学显微镜下对配子体发生进行了观察、描绘和照相.
  
• The production of massive protonema immediately follows and then caulonema, chloronema and secondary rhizoides.
  孢子萌发后直接产生块状原丝体;块状原丝体上产生轴丝体 、 绿丝体和次生假根.