BIO 200 Lecture Notes - Lecture 13: Symbiogenesis, Cell Membrane, Protist

19 views5 pages

Document Summary

Origin of the eukaryotes: earliest eukaryotes, eukaryotic traits, origin of organelles, endosymbiosis: mitochondria and chloroplasts. Protists: protists are not monophyletic, protists traits, building the bridge to multicellularity. Types of protists: alveolates, stramenopiles, rhizarians, excavates, amoebozoans, choanoflagellates. Allows for flexibility deal with environment in new ways because of differentiation of cell types into organs and tissues. Lose rigid prokaryotic cell wall allows more fluid plasma membrane to fold in on itself creates more surface area without increasing size allows for larger surface for gas and nutrient exchange: formation of organelles. Once cell surface folds in, it can pinch off and bring in items from outside the cell into itself endocytosis. When membrane folds, new structures can be created: endosymbiosis leading to mitochondria and chloroplasts - know figures! Ancestral eukaryotic cell engulfed an aerobic energy producing bacterium didn"t digest it. Arrangement became permanent in a way that bacteria can"t live outside eukaryotic cell. Eukaryotic cell is also dependent on bacterium.