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Bacteria. Salmonella spp. Escherichia coli. MRSA. 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.
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Bacteria Salmonella spp.
Escherichia coli MRSA
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.
Eubacteria • This group includes the traditional bacteria and is the largest of the two.
Bacteria are everywhere! • They are found in nearly every habitat studied, including some that no other organism is able to withstand
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.
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.
Bacterial shapes • Cocci – spherical • Diplococci– pair • Streptococci - chain • Bacilli - rod-shaped • Spirochete – spiral
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.
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.
Video: Big Bang • http://www.youtube.com/watch?v=mx8itzrdV7I • http://www.ryancshaw.com/Files/micro/Animations/BacterialGrowth/PLAY_bacterial_growth.html • Cell phones and bacteria • http://www.teachertube.com/viewVideo.php?title=Cell_Phone_Bacteria&video_id=15882