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Ferns and Mosses

In the gametophyte generation ferns have Haploid cells. The fern spore develops into a small, heart-shaped gametophyte (prothallus) that sustains itself by photosynthesis. Their eggs are formed in archegonia and their sperm are formed in antheridia. Archegonium is the female gametangium which is a moist chamber in which gametes develop in plants. Antheridium is the male gametangium which is a moist chamber in which gametes develop in plants. A Fern’s gametophyte is photosynthetic and has rhizoids for anchoring and water absorption. Ferns are parasitic only temporarily. Their foot and stalk are parasitic upon gametophytes. They become independent and develop new structures which are roots, stems, and leaves. Their spore cases are formed on the leaves. Their tissues then simplify. Moss gametophytes

The sperm transport and fertilization in ferns begins with sperm swimming to archegonium and require dew, moisture, etc., for transport. The neck canal cells and ventral canal cell of the archegonium disintegrate. Disintegration of cells may form a chemical that attracts sperm. Fertilization occurs in venter of the archegonium. When the gametophores of mosses are mature, they produce gametes in gametangia. Eggs are produced singly in vase-shaped archegonia, and large numbers of sperm are produced in elongate antheridia. Jackets of protective tissue enclose both types of gametangia. Moss gametophytes can produce many archegonia and antheridia which are typically born on separate male and female plants. Flagellated sperm are released into water films in which they swim toward eggs, passing down the op