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Bacteria. From Bacteria to Plants Chapter 2.2 Pages 56-66. Discovery. Believed to be one of the earliest forms of life on Earth Undiscovered until the 1600’s Anton van Leeuwenhoek. Bact Basics. Bacteria are Prokaryotes : genetic material is not contained in a nucleus
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Bacteria From Bacteria to Plants Chapter 2.2 Pages 56-66
Discovery • Believed to be one of the earliest forms of life on Earth • Undiscovered until the 1600’s • Anton van Leeuwenhoek
Bact Basics • Bacteria are Prokaryotes: genetic material is not contained in a nucleus • Also lack many other structures found in cells.
Shape & Structure • Most bacteria have Cell Walls, for protection • Also has… • Cytoplasm that contains genetic material • Ribosomes which produce proteins • Flagellum (flagella) a whip-like structure / tail used for movement.
Shape & Structure Three basic shapes • Spherical • Rod-like • Spiral shaped • These shapes help us identify bacteria
Tale of Two Kingdoms Archaebacteria Eubacteria Original autotrophs(produce their own food) that developed our atmosphere Live in all non-extreme environments The surface of any object On animals Inside animals • “Ancient,” having existed for billions of years • Live in extreme environments • Hot springs • High salinity • High acidity
Reproduction • Bacteria reproduce through process called Binary Fission • Cell copies its genetic material then divides into two separate cells.
By the Numbers • The average surface in your bathroom contains about 6,000 bacteria per square inch • Disinfectants claim to kill 99.9% of germs • This would leave 5 bacteria… not bad • However, average sink space is about 2 square feet – leaving 120 bacteria behind.
By the Numbers • Under decent conditions, binary fission can take place every 30 minutes • After an hour, each bacteria will reproduce 2x, creating 480 bacteria • It will take only 3 hours to create 7,680 bacteria where there was only 5 before.
What to Work On • Finish reading about Bacteria in your textbook, pages 56-65 • Working as a group, answer the section review questions on page 65 (#’s 1-5) • One answer page per group