This will provide a better distribution of spores downwind. Mosses can also reproduce asexually by fragmentation or by growing little vegetative buds called gemma, which can break off and grow into a new plant. Division Tycophyta contains species that represent a distinct line of evolution out of the first land plants. The sperm swim in this water film to the open archegonium. Examine the living whisk ferns on display. When it first begins to uncurl, the frond looks like the scrolled neck of a violin or fiddle, and this stage of development is called a fiddlehead. The Lycopodium gametophyte produces both antheridia and archegonia.
New York: Springer-Verlag, Examine the living horsetails on display. Seedless plants includes lycophytes, ferns, horsetails. True mosses are nonvascular plants whose most commonly recognized life form is a gametophyte, and true rushes are grasslike flowering plants. But mosses are surprisingly resistant to drying up, and can survive under very harsh conditions. Biology of Plants, 6th ed. The blade of the fern is called a frond, and the little individual leaflets are called pinnae.
Seedless Vascular Plants
Farabee at Estrella Mountain Community College. Mosses are the most abundant plants in both the Arctic and the Antarctic. The ferns and fern allies germinate from spores. In some species the sporophylls are mixed in with the scale-like leaves. In both lycophytes and seed plants, heterospory evolved, as did endosporial development of the megagametophyte. A rhizome is a horizontal stem that spreads the plant around. In the axil of the enations, a sporangium may form.
The tiny gametophyte may be either autotropophic like the fern prothallus or heterotrophic like the gametophytes of some lycopsids , and is generally free living and independent of the parental sporophyte. Later they became larger d and were vascularized e. Second, all plants need to get water to their cells. Contrast these primitive vascular plants with the more advanced seed plants, the gymnosperms and angiosperms, which germinate from seeds rather than from spores. The sperm swims to the egg to fuse into a diploid zygote. Its small size lets it rely entirely on diffusion.
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