plant diversity and non-seed plants

plant diversity and non-seed plants - Biology 5B Plant...

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Unformatted text preview: Biology 5B Plant Diversity Overview: The Greening of Earth For more than the first 3 billion years of Earths history, the terrestrial surface was lifeless Since colonizing land, plants have diversified into roughly 290,000 living species Plants supply oxygen and are the ultimate source of most food eaten by land animals The advent of plants on earth cant be understated because they helped make the atmosphere we now enjoy (and require!) possible Green algae Amoebozoans Opisthokonts Alveolates Stramenopiles Diplomonads Parabasalids Euglenozoans Dinoflagellates Apicomplexans Ciliates Diatoms Golden algae Brown algae Oomycetes Excavata Chromalveolata Rhizaria Chlorarachniophytes Forams Radiolarians Archaeplastida Red algae Chlorophytes Charophyceans Land plants Unikonta Slime molds Gymnamoebas Entamoebas Nucleariids Fungi Choanoflagellates Animals Even some of the earliest plants are protists Plants evolved from protists generally and from green algae more specifically CONCEPT: Land plants evolved from green algae Green algae called charophytes are the closest relatives of land plants Green algae Amoebozoans Opisthokonts Alveolates Stramenopiles Diplomonads Parabasalids Euglenozoans Dinoflagellates Apicomplexans Ciliates Diatoms Golden algae Brown algae Oomycetes Excavata Chromalveolata Rhizaria Chlorarachniophytes Forams Radiolarians Archaeplastida Red algae Chlorophytes Charophyceans Land plants Unikonta Slime molds Gymnamoebas Entamoebas Nucleariids Fungi Choanoflagellates Animals Even some of the earliest plants are protists Plants evolved from protists generally and from green algae more specifically CONCEPT: Land plants evolved from green algae Green algae called charophytes are the closest relatives of land plants Adaptations Enabling the Move to Land In charophytes (and their ancestors) a layer of a durable polymer called sporopollenin prevents exposed zygotes from drying out. This adaptation allowed them to take advantage of an open niche in habitats and move onto land Charophyte ancestors lived at the waters edge where they had access to unfiltered sun, more plentiful CO 2 , nutrient rich soil and fewer herbivores and pathogens But, land presented challenges: a scarcity of water and lack of structural support Eukaryotic common ancestor Rhodophyta (red algae) Chlorophyta (green algae) Charophycean Embryophytes algae (land plants, kingdom Plantae ) Mainly in marine/freshwater habitats Plants probably had a monophyletic eukaryotic origin and first appeared in aquatic habitats (but read your text about other hypotheses) Red Algae from intertidal of San Diego Rhodophyta Chlorophyta Volvoxin pond water Charophycean Musk grassin pond water ANCESTRAL ALGA Red algae Chlorophytes Charophytes Embryophytes Viridiplantae Streptophyta Plantae Multicellular Eukaryotic Photosynthetic Autotrophic Cells of cellulose (and other materials) Many biochemical details Common Features Between Charophytes and Land Plants Derived Traits of Plants...
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plant diversity and non-seed plants - Biology 5B Plant...

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