Biological Diversity BSCI 10110 1 MWRF 1 10 2 00 Dr Mark Kershner Week 6 10 5 Ebola hemorrhagic fever fruit bats spread in saliva of fruit bats chimpanzee mountain gorilla duiker spread to humans due to poaching Amoeba Acanthamoeba polyphaga can be infected by largest know virus mamavirus creates virus factories inside mamvirus were Sputniks viruses inside the virus next tested whether Sputniks were replicating within mamavirus Sputniks injected into an amoeba had no effect on amoeba did not replicate yes virophage Sputniks harmed mamavirus led to deformed viral particles amoeba growth increased with Sputniks decreased energy use by mamavirus 3 fold decrease in amoeba lysis 70 fewer infective particles in amoeba cultures Prions simple proteins misfolded much smaller than viruses have no genome Fig 27 10 normal prion protein and misfolded prion protein the two prion proteins touch and produce only misfolded accelerated rate of change in protein shape accumulates on neurons changes them transmissible spongiform encephaliopathies chronic wasting disease deer elk cattle mad cow disease sheep scrapie can pass to humans Creutzfeldt Jakob disease Kuru cannibalistic ritual Papuan New Guinea significant cluster of Creutzfeldt Jakob disease prions can lay dormant for decades decline since 1950s fewer people are partaking in ritual cattle deer deer get it from picking on carcasses cattle were fed bonemeal from bones offal innards grind it up bonemeal added to cattle feed become infected people consume this beef infected spongiform encephalopathy in humans Prion protein PrPc normal form or PrPsc misfolded form Number of cattle infected increased from 1985 peaking in 1990 and dropping in 1995 drop due to cattle death disease slaughtering became unlawful to feed cattle in this fashion in England by 1999 163 dead humans in England and 37 from elsewhere approximately 460 480 thousand cattle likely infected that entered the human food chain 10 7 How are certain viral diseases transmitted Ebola gorillas chimps duikers humans through poaching hunting sampled invertebrates and vertebrates to identify reservoir fruit bats spread it through discarded fruits SARS severe acute respiratory syndrome passed between people through respiratory passage originally tracked to civets cat fox passed to humans through respiratory or primary reservoir was nocturnal bats passed to civets or passed directly to bodily fluids humans food source Hantavirus Prion proteins rodents deer mice chipmunks humans through feces dried urine normal form and misfolded form differ in shape when misfolded touches a normal the normal gets converted misfolded accumulates along nerve cells and damages the cells Prokaryotes Chapter 28 domains bacteria and archaea simplest oldest life forms filaments linked rods fossil approximately 3 5 billion years old 2 billion years ago O2 appears microfossils evidence of lipid molecules C fixation Prokaryotes vs Eukaryotes Prokaryotes inorganic C organic C before nucleus 1 all single celled filaments colonies 2 small cells 3 circular DNA one large genome few small plasmids 1um 1 1millionth of a meter Eukaryotes small rings of genetic information not part of genome horizontal gene transfer 4 cell division binary fission 5 no nucleus no membrane bound organelles no compartmentalization of internal area true nucleus 1 multicellular some unicellular organisms protests 2 larger cells at least 10 times larger than prokaryotes 3 linear DNA directly associated with the chromosomes 4 cell division mitosis complex process by which chromosomes are pulled to opposite sides poles of a cell prior to division occurs 5 nucleus membrane bound organelles compartmentalization 10 8 Prokaryote vs Eukaryotes continued Prokaryotes 6 Flagellum simple single protein fiber flagellin flagellin is like a propeller 7 Energy photosynthesis light energy CO2 O2 produce sulfur sulfate chemolithoautotrophs oxidizing inorganic molecules gaining energy stored in bonds Eukaryotes 6 Flagellum protists algae whip like action complex structure of microtubules characterized by 9 2 structure two surrounded by nine 7 Energy photosynthesis chloroplasts plants protists algae cellular respiration mitochondrion What do prokaryotes do decomposition breakdown of organic water inorganic matter produce O2 live in extreme environments where no eukaryotes can go digestion in many organisms food additive yogurt cheese alcohol fermentation potentially very long lived resting stage hugely important in nutrient cycling ex nitrogen disease food for other organisms major role in food web can produce methane some prevent fight infection enhancing health used in drug production pharmaceutical processes genetic engineering natural pesticides bioterrorism anthrax Prokaryotes Bacteria Archaea rod shaped spherical oval spiral helical rod shaped bacteria form filaments individual bacteria linked Archaea Bacteria plasma membrane archaea glycerol and hydrocarbon with ether bond bacteria glycerol and hydrocarbon with ester bond cell wall strengthens the structure of the individual prokaryote peptidoglycan only in bacteria increases the strength of the cell wall 10 9 Exam 2 next Friday 10 16 Chapter 22 begins with speciation Chapter 23 phylogenetic tree Chapter 26 tree of life Chapter 27 viruses prions RNA virus vs DNA virus RNA flu HIV DNA poxes Chapter 28 prokaryotes Bacteria vs Archaea Fig 28 3 plasma membrane Fig 28 4 bacteria ester bonds between glycerol and hydrocarbons archaea ether bonds between glycerol and hydrocarbons difference in lipid structure within the plasma membrane structure protection bacteria a major component is peptidoglycan protein cell wall increases stability alters patterns of food uptake archaea no peptidoglycan DNA replication and protein production bacteria lack introns in their genes archaea structure of genes introns removed prior to protein production alters gene expression share with eukaryotes introns and exons alternate introns removed from sequence Archaea extreme environments some not so extreme small relative to bacteria often live anaerobically without O2 very hot very cold low pH acidic high pH alkaline salinity high salinity most are autotrophs self feeding photosynthetic metabolize H2S consume organic matter Thermophiles 60 80 C 140 175 F Yellowstone geysers hot springs volcano pigmented biofilm deep sea geothermal vents high temperature environments H2S hydrogen sulfide used as an energy source Methanogens produce methane
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