The stem, or rhizome, of a fern grows horizontally through the soil. Tiny curled-up fronds (leaves) grow from small buds on the rhizome. The buds unroll and the frond expands. The fronds of some ferns grow 20 ft (6 m) long, but others reach only 1/2 in (13 mm).
Most mosses grow in short clumps, or cushions. They do not have true roots, but short, slender growths, called rhizoids. Rootlike rhizoids anchor moss to soil, rock, or bark, but do not draw up water. Instead, leaves absorb moisture in the air.
The leafy tips of mosses produce male and female sex cells. Male sex cells swim through water on the surface of the plant to reach and fertilize female cells. Fertilization produces a stalked sporophyte, or spore capsule, that scatters spores into the air.
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