Practice question

In seedless vascular plants including lycophytes and ferns, sexual reproduction retains ancestral dependence on external liquid water for syngamy. Male gametophyte antheridia release numerous multiflagellated, coiled spermatozoids that must swim through continuous water film to reach archegonial neck and fertilize stationary egg inside venter. Eggs and spores are non-motile, gametophyte may be aquatic but chief mechanism is flagellated sperm requiring swimming medium. Seeds later eliminated this need via pollen tube delivery, but pteridophytes still need moist conditions. This structural framework illustrates phylogenetic relationships and adaptive significance highlighted in competitive examinations focusing on comparative plant morphology and systematics.