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Published byApril Russell Modified over 9 years ago
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BACTERIA
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1. Bacteria are classified into two kingdoms: Eubacteria (true bacteria) and Archaebacteria (Ancient Bacteria). 2. BACTERIA are microscopic Prokaryotes. (“before nucleus”) 3. Adapted to living in all environments (even some extreme) – they exist EVERYWHERE Just keep swimming.....videoust keep swimming.....video
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Binary fission is the splitting of a parent cell into two daughter cells; it is asexual reproduction in prokaryotes. II. Reproduction in Prokaryotes
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In bacteria, genetic recombination can occur in three ways. a. Conjugation occurs when a bacterium passes DNA to a second bacterium through a tube (sex pilus) that temporarily joins two cells; the plasmid (DNA) is then exchanged
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Transformation involves bacteria taking up free pieces of DNA secreted by live bacteria or released by dead bacteria.
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Transduction, bacteriophages transfer portions of bacterial DNA from one cell to another.
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III. Prokaryotic Nutrition 1. Bacteria differ in their need for, and tolerance of, oxygen (O 2 ). a. Obligate anaerobes are unable to grow in the presence of O 2 ; this includes anaerobic bacteria that cause botulism, gas gangrene, and tetanus. b. Facultative anaerobes are able to grow in either the presence or absence of gaseous O 2. c. Aerobic organisms (including animals and most prokaryotes) require a constant supply of O 2 to carry out cellular respiration. staphylococcus is a gram-positive, facultative anaerobe
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2. Autotrophic Prokaryotes a. Photoautotrophs use light energy to assemble the organic molecules they require. b. Chemoautotrophs make organic molecules by using energy derived from inorganic compounds in the environment. (methanogens) Check out the virus and bacteria gallery
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THERMOACIDOPHILE – the red stuff on the rocks This is an archaebacteria. THE FUTURE BELONGS TO ARCHAE!
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3. Heterotrophic Prokaryotes a. Most free living bacteria are chemoheterotrophs that take in pre-formed organic nutrients. b. Some are symbiotic Bacteria have an important role to play in breaking down materials in the environment. Some are harmful and break down material we'd rather keep, like this image of an infection of necrotizing fasciitis (flesh-eating bacteria )
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Mutualistic nitrogen- fixing Rhizobium bacteria live on roots of soybean, clover, and alfalfa where they reduce N2 to ammonia Mutualistic bacteria that live in the intestines of humans benefit from undigested material and help us break down food
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Bacteria Shape & Naming The Gram stain procedure (developed in the late 1880s by Hans Christian Gram) differentiates bacteria. a. Gram positive bacteria stain purple, whereas Gram negative bacteria stain pink. b. This difference is dependent on the thick or thin (respectively) peptidoglycan cell wall.
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Bacteria Shapes Cocci – spheres Bacilli – rods Spirilla - spirals Staph – in clusters Strep – in chains
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Streptococcus
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Gram Stain Procedure
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Gram Negative
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Gram Positive
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Identify Gram Negative, Bacillus
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Gram Positive, Bacillus (Anthrax)
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Identify Gram Positive Staphylococcus
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Streptococcus - Strains are responsible for strep throat, and flesh eating bacteria Bacteria and Health
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Staphylococcus aureus Staph means “bunch of grapes” in greek.
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Bacillus subtilis Easy to grow in the lab, not harmful Gram Positive *this is an example of a "poor" stain, it looks both pink and purple. Gram staining takes practice
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Bacillus tetani -Tetanus Rigid muscles from tetanus infection Also known as “lockjaw”
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Clostridium botulism Gram positive Causes food poisoning that is sometimes fatal All forms lead to paralysis that typically starts with the muscles of the face and then spreads towards the limbs.[1] In severe forms, it leads to paralysis of the breathing muscles and causes respirator y failure. In view of this life- threatening complication, all suspected cases of botulism are treated as medical emergencies, and public health officials are usually involved to prevent further cases from the same source.[1]
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A form of botulism is used in BOTOX treatments, as it paralyzes the muscles of the face and effectively smooths wrinkles. Results may vary.
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Yersinia Pestis The black plague, this bacteria was carried on the fleas of rats. It was responsible for the deaths of thousands of Europeans from the 8th to the 14th century.
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Bacillis Anthracis (Anthrax)
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Mycoplasmas Causes pneumonia Rickettsia rickettsi Rocky Mountain Spotted Fever, carried by ticks
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E. Coli
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Salmonella
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Plush Germs SyphilisE. Coli
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Gonorrhea The Plague (Black Death)
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