BIO 121 Lecture Notes - Lecture 18: Lycopodiopsida, Meristem, Gametangium
Document Summary
Plant evolution is marked by adaptations to living on land. Are the closest living relative of plants. Proteins arranged in cellulose for cell walls cytokinesis. Alternation of generations : plants alternate b/w two multicellular generation. Key traits appear in almost all plants but are absent in charophytes. Embryo is dependent on the parent plant; lives inside the female gametophyte"s tissues. Makes them tough and resistant to desiccation. Plant gametes are produced in organs called . Plants are classified based on the presence of key adaptive features. Most similar to the first plants, which evolved 475 mya. Live as a part of the gametophyte; depend on it for nutrition. Plants need n to live, but can"t fix" it themselves. Mosses maintain n in soil. in n scarce forests, mosses harbor n-fixing cyanobacteria, which incorporate n from the air. Moss is a large component of a type of partially decayed organic material called .
