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VIRUSES (What the heck are they?). The Common Cold Virus. Oh Goodness, My E. coli has a Virus!. Viruses and Bacteria. It's easy to mix these up since compared to us, both are. VERY SMALL. Great link for size comparison! Source: http://www.cellsalive.com/phage.htm.
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Oh Goodness, My E. coli has a Virus! Viruses and Bacteria It's easy to mix these up since compared to us, both are VERY SMALL. Great link for size comparison! Source: http://www.cellsalive.com/phage.htm
The basics Viruses are: non-living much smaller than the smallest cell pieces of genetic coding (DNA or RNA) “gift-wrapped” in a protein coat
Diseases caused by viruses include: • Common cold • Flu • Polio • Rabies • Herpes (chickenpox,cold sores, genital) • Warts • Measles, Mumps • Ebola • AIDS Viruses cannot be killed with antibiotics because they are not alive!
Diversity of Life Introduction to Prokaryotes
Two types of Prokaryotic organisms: Eubacteria (bacteria) and Archaea Prokaryotes Domain Bacteria Domain Archaea (e.g., extremophiles) Visual Summary 15.3
Archaea – Halophiles in seawater evaporating ponds near San Francisco Bay. Salinity increases from 3% to 20% during the production of salt.
Archaea (a.k.a. “Archaeabacteria) · Prokaryotic (like eubacteria) · Biochemically resemble eukaryotic cells · Believed to be the ancestors of eukaryotic cells ·Today: only live in harsh environments
Bacteria on the tip of a pin.
Major Episodes in the History of Life Millions of years ago Major Episode 475 570 1,000 1,700 2,500 3,500 4,500 Plants and fungi colonize land All major animal phyla established First multicellular organisms Oldest eukaryotic fossils Accumulation of atmospheric 02 Oldest prokaryotic fossils Origin of Earth Visual Summary 15.1
ALL CELLS have • Plasma membrane • DNA • ribosomes
Detriments to Humans • Bad breath, tooth decay • Food poisoning • Some are pathogenicpathogenic –
Some Diseases caused bybacteria • Strep throat • Cholera • Tubercolusis • “the plague” • Anthrax • Toxic shock syndrome • Syphilis, Gonorrhea,
How cure bacterial infections? (Antibiotics)
Discussion Question:Should we drop “bacteria bomb?” • Are there benefits to bacteria that outweigh their detriments to humans????
Benefits of Bacteria • Decomposers! chemical cycling • Cyanobacteria were original producers of oxygen atmosphere ozone • Origins of mitochondria & chloroplasts • Aid humans in digestion (E. coli) • Allow cows to digest cellulose (grass) milk, ice cream, hamburgers! • Lactic acid fermentation (yogurt, buttermilk, sauerkraut) • bioremediation • Nitrogen “fixers” (to be explained in Unit IV!)