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TAKS. Bacteria and Viruses. A sore throat?. Pimples?. Chicken pox?. A cold sore or fever blister?. Have you ever had…. A sore throat?. Pimples?. Chicken pox?. A cold sore or fever blister?. What causes these?. Bacteria. Viruses. What are bacteria?. Eubacteria: “true bacteria”
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TAKS Bacteria and Viruses
A sore throat? Pimples? Chicken pox? A cold sore or fever blister? Have you ever had…
A sore throat? Pimples? Chicken pox? A cold sore or fever blister? What causes these? Bacteria Viruses
Eubacteria: “true bacteria” Includes common bacteria like E. coli Live nearly everywhere Two Types • Archaebacteria: “ancient bacteria” • Live in places where it is very hot, very acidic and very salty • Oldest group of bacteria on Earth
Bacteria - characteristics • All are prokaryotes • All are microscopic—too small to see with your eyes • They live everywhere • Come in three shapes: round, rod and spiral
Bacteria - shapes Spiral shape: spirilla Round shape: coccus Rod shape: bacillus
Bacteria - structure Cell membrane flagella DNA ribosome pili cytoplasm cell wall
Viruses • Viruses are tiny non-living things that have some characteristics of living things: • They have genetic material • They can reproduce but they need a hostcell to help them
Virus - characteristics • They are smaller than cells. • They are parasites—they need a cell to reproduce. • They are specific—they will only infect certain cells • For example: Flu virus only affects cells in the respiratory system