BIO153H5 Lecture Notes - Lecture 9: Red Algae, Sporophyte, Anisogamy

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6 Dec 2013
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Plants are a clade composed of the green algae or chlorophyta (which are classified in cotemporary taxonomies as protists) and the land plants. Green algae vary a great deal in their structure (some are unicellular; some colonial, some multicellular etc. ), but in many ways they are similar to land plants: they have: chloroplasts with double membranes chlorophyll a & b cellulose in the cell wall. The first fossils of green algae are from ~700 million years ago, and a corresponding rise in. O2 levels is observed in the geological record. (my favourite green alga: chlamydomonas nivalis, which causes watermelon snow!) Green algae are ecologically important today because of their contribution to global photosynthesis. Also: green algae in symbiosis with fungi form lichen some live as endosymbionts in protists. Plants may be extremely long-lived: some individuals of the creosote bush (larrea spp. ) may be greater than. 14,000 years old (longer than recorded human history)!