3.有性繁殖的迸化雌雄有别 http://en.wikipedia.org/wiki/Evolution_of_sexual_reproduction 有性繁殖起源于120亿年前的单细胞真核生物 衣藻与蕨类的性生活 Fern Life Cycle Mitosis Chlamydomonas Sporophyte Indusium Sorus with many Fronds covering a sporangia Meiosts life cycle sors Spores F月dlehead Mitosis Annulus Young Diplold (2N) Roots Haplold (N) Prothallus Fertilization Sperm Germinating spore E99 Meiosis Rhizoids hollow ertiltratio cell wall Antheridium Gametophyte 102016/11/24 1 10 3. 有性繁殖的进化-雌雄有别 http://en.wikipedia.org/wiki/Evolution_of_sexual_reproduction 有性繁殖起源于 120亿年前 的单细胞真核生物 衣藻与蕨类的性生活