Protista - mosses, liverworts, hornworts. Divided into...

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Protista (Protoctista): algae, amoebae, flagellates, sporozoans, ciliates, water molds, diatoms, slime molds, etc. No completely satisfactory way to classify this extremely diverse group Not plants; eukaryotes many with plant-like features (chlorophyll, photosynthetic, cellulose in walls), others like fungi (filamentous), some animal-like (ingest food); unicellular, multicellular, colonial; mostly aquatic, both marine and freshwater Oldest eukaryote may be a brown-alga-like fossil 1.7 billion years old; or another presumed photosynthetic eukaryote found in 2.1- billion-year-old rocks; acritarchs (fossilized shells of shelled amoebas) first found in rocks 1.5 billion years old Importantance: plants, animals, and fungi all derived from ancient protists; plant ancestor a green alga very much like green algae of today Plantae– Bryophytes:
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Unformatted text preview: mosses, liverworts, hornworts. Divided into three groups: Bryophyta (mosses), Hepaticophyta (liverworts), Anthocerotophyta (hornworts) Small, nonvascular plants; body a thallus; gametophyte is free-living and the prominent plant; the sporophyte small, dependent upon the gametophyte; both sexual and asexual reproduction present; motile (flagellated) sperm require water in which to reach the egg Ancestors of bryophytes probably derived from a green alga ancestor; oldest fossil bryophytes in 350 million years old rocks (younger than first vascular plant fossils, but probably because bryophytes lack resistant tissues for preservation) Three groups are of different lineages, liverworts the oldest; mosses important in the ecology of the arctic and subarctic; some commercial usepeat for fuel, Sphagnum as packing material...
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