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Bacteria Salmonella spp.
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Escherichia coli MRSA
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Prokaryotes vs Eukaryotes
There are two basic types of cells: prokaryote and eukaryote. Plants, animals and fungi are eukaryotes: meaning they have a true nucleus. Prokaryotes are single-celled organisms. All bacteria are prokaryotes. They are the smallest, simplest organisms.
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Eubacteria This group includes the traditional bacteria and is the largest of the two.
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Bacteria are everywhere!
They are found in nearly every habitat studied, including some that no other organism is able to withstand
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General Structure of a Bacterium
Bacteria have : a cell wall a cell membrane no membrane-bound organelles such as a nucleus, mitochondria, chloroplasts, Golgi apparatus, or ER.
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Movement: Cilia and Flagella
Some bacteria are able to move using special cell structures called cilia and flagella. Cilia are hair like Flagella are tail-like By repetitive beating (like a bending motion), they cause the cell to move. Think of oars in a boat.
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Bacterial shapes Cocci – spherical Bacilli - rod-shaped
Diplococci – pair Streptococci - chain Bacilli - rod-shaped Spirochete – spiral
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Asexual reproduction: Fission
Prokaryotes reproduce by simply splitting in two in a process called binary fission. The DNA is copied and the cell divides into two identical cells.
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Sexual reproduction: Conjugation
Sexual reproduction combines genes from two different individuals and increases variation. Conjugation - Two cells join briefly and one cell donates some DNA (called a plasmid) to the other one.
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Video: Big Bang http://www.youtube.com/watch?v=mx8itzrdV7I
Cell phones and bacteria
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