Lecture 25 Microbial World PDF

and carbon ? how do organisms get energy Lecture 25 microbial world !...

and carbon ? how do organisms get energy Lecture 25 microbial world ! CARBON all need carboni organisms Three Domains of life food from autotrophs generate their own inorganic molecules 1. ) Archaed.) Bacteria 2 heterotrophs consume food produced by other organisms 3 ) Eukarya. chemotrophs energy comes directly from chemical reactions phototrophs energy comes from light Note ! not all photoautotrophs do Eukaryotes include plants animals , , fungi, and most algae ! Oxygenic photosynthesis They all have: > a nucleus - > - linear chromosomes ENERGY > - Mitochondria > - sexual reproduction DO DO NOT ↳ Aerobic vs. anaerobic metabolism live * can the organism in the presence of oxygen ? PROKARYOTES : Small cells without nucleus specialized a or organelles cell structure : lack membrane-bound organelles , DNA not enclosed in a nucleus Archaea (prokaryotes ↳ extremophiles w/anaerobic metabolisms size : typically smaller generally Reproductioreproduceasexuallythroughbinary fission places w/out a - must occur in O2 contain additional Small DNA molecules called plasmids ! ↳ found in harsh anoxic environments of extreme salinity or extreme temps ! - ex/ in animal guts or under kilometers of ice EUKARYOTES : larger cells with DNA packed into a membrane-enclosed nucleus and membrane enclosed organelles to compartmentalize cellular processes ↳someareChemoautotrophsthatthrivearoundvoanivesa cell structure : membrane-bound organelles; DNA rich in hydrogen Sulfide enclosed in nucleus size larger : Reproduction Reproduce : both asexually and sexually Genetic material multiple linear chromosomes : Bacteria (prokaryotes) contained within the nucleus ↳ highly diverse group that contains species that live by metabolism possible virtually every mode of nutrition and um ↳ parasites and pathogens mutualism Don some are , others in ↳ many critical roles decomposers of organic others play as matter that recycle nutrients in the environment and as ↳ after ↳ chromosomes doubling symbionts in animal guts in size, areseparated and single cell nucleus splits before two cells splits into the cell divides > - anoxygenic cyanobacteria O methanogens = earliest organisms CYANOBACTERIA EARTH -