Explain the dependence of ferns’ sexual reproduction on water.

Lower plants, which include ferns, have an imperfect process of sexual reproduction. The resulting gametophyte bears both female and male parts. Anatomically, they are disproportionately located, the male archegonia are on the periphery, and the female antheridia are below the center. Fern spermatozoa are not able to reach the eggs on their own under normal conditions; this requires water. Thus, the fusion and formation of a zygote occurs, which will give rise to a sporophyte.