![]() Sexual reproduction : antheridia are on round topped stalks.Īrchegonia are on palm tree like stalks ( with lobes instead of a circular disc on the top). Sporangium may have elaters to shoot out the spores.Īsexual reproduction by gemmae, which are dispersed by rain.Įxample : Marchantia the gametophytes are dioecious (separate males and females ) Fossils Liverworts are restricted to wet areas : lack cuticle, and lack vascular tissue. Liverworts and mosses are the oldest land plants, with fossils dating back almost 500 million years. Sphagnum moss releases its spores in an explosive burst.Ħ,000 species. It stores water in dead cells and creates acid conditions in peat bogs. Sphagnum can hold 20 times its own weight of water. ![]() Spores are wind dispersed : some species have peristome teeth around theĬapsule to release spores in dry weather.Įxample : Sphagnum peat moss ( used commercially for holding moisture in the soil). ![]() Mosses need water to reproduce : antheridia produce sperm and archegonia produce eggs. They are gametophyte dominant (the gametophyte lasts much longer than the sporophyte). There are two main phyla of spore plants that lack vascular tissue. The sporophyte, in turn, produces haploid spores by meiosis which grow into another haploid gametophyte.įrom : gametophyte dominant To : sporophyte dominantįrom : need water for reproduction To : no water needed BSC 2011C Chapter 27 : Spore Plants Chapter 27 Plant Kingdom (Spore plants) Characteristics of plants :Ĥ) usually terrestrial (growing on land) : waxy cuticle (reduces water loss)ĥ) alternation of generations : a haploid gametophyte produces gametes that fuse to form a diploid sporophyte. ![]()
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