EEMB 3 Lecture Notes - Lecture 8: Nuclear Material, Protist, Cytoskeleton
21 Apr 2019
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Q: which is not a major step to the transition from the prokaryote to the ancestral eukaryote: loss of cell wall, used cytoskeleton for structural support, formation of nucleoid, endosymbiosis of some organelles, all are major steps. No membrane separating transcription & translation (everything in cytoplasm) Ribosomes are slightly smaller & distributed across cytoplasm. Separation of transcription (in the nucleus) & translation (in the cytoplasm) Needed to get larger to code for more sophisticated functions. Loss of cell wall flexibility -- lower surface area to volume ratio. Fixed this problem by infolding surface area to combat low ratio. Infolds allow greater surface area to volume ratio, but is still less than prokaryotic organisms. Infolds started to surround nucleus development of membrane bound nucleus. Appearance of cytoskeleton physical structure to big cells. Prokaryotes digest externally, eukaryotes are bigger so it"s more efficient to digest internally. Ingestion of another organism, but not the digestion. Most are aquatic/live in a fluid system.
