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Bacteria

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Can make their own food (autotroph) or obtain food from the ... Spirillum)- spiral and corkscrew shaped. Cell Walls. 2 Types in Eubacteria. Gram positive ... – PowerPoint PPT presentation

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Title: Bacteria


1
Bacteria
  • Living Prokaryotes

2
Bacteria Vocab
  • Prokaryote photoheterotroph
  • Bacillus chemoautotroph
  • Coccus binary fission
  • Spirillum conjugation
  • Flagellum endospore
  • photoautotroph

3
Prokaryotes
  • Bacteria are prokaryotes.
  • Prokaryote- single-celled organisms that lack a
    nucleus.

Nope! No Nucleus Here!
4
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5
2 Kingdoms of Bacteria
  • Eubacteria
  • Archaebacteria

6
Eubacteria Review
  • Larger of the two kingdoms.
  • Live almost everywhere.
  • Unicellular
  • Microscopic
  • Can make their own food (autotroph) or obtain
    food from the environment (heterotroph)
  • Surrounded by a cell wall that contains a
    carbohydrate called peptidoglycan.

7
Examples of Eubacteria
  • the bacterium that causes the disease anthrax,
    Bacillus anthracis--E. coli, a common inhabitant
    of the gut--Streptococcus (one species causes
    strep throat)--Clostridium botulinum (causes
    botulism)--Oscillatoria (a common photosynthetic
    bacterium found in freshwater ponds)

8
Archaebacteria Review
  • About the same size as eubacteria.
  • No nuclei
  • unicellular
  • No peptidoglycan in their cell walls.
  • Membrane lipids are different.
  • DNA is more similar to eukaryotesreason why
    scientists think they may be the ancestors of
    eukaryotes.

9
Examples of Archaebacteria
  • thermophiles
  • halophiles

10
Bacteria are identified by
  • Shape
  • Cell Walls
  • Movement

11
Shape
  • Bacillus (pl. Bacilli)- rod-shaped
  • Coccus (pl. Cocci)- sphere-shaped
  • Spirillus (pl. Spirillum)- spiral and corkscrew
    shaped

12
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13
Cell Walls
  • 2 Types in Eubacteria
  • Gram positive
  • Gram negative
  • Gram positive look purple in microscope because
    they have peptidoglycan that absorbes dye.

14
  • Gram negative bacteria that look pink because
    cell walls contain carbohydrates that absorb only
    red stain.

Helicobacter Gram negative
Anthrax Gram positive
15
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16
Movement
  • May use flagella
  • Whip-like structures used for movement.
  • Lash, snake, or spiral forward
  • Glide along slime
  • Some do not move at all

17
Obtaining Energy
  • Autotrophs
  • Photoautotrophs use light for food
  • Chemoautotrophs use chemicals
  • Heterotrophs
  • Photoheterotrophs capture sunlight but also
    need organic compounds

18
Bacteria Growth and Reproduction
  • Grow and divide very quickly.
  • - Some every 20 minutes.
  • Binary Fission-
  • Asexual form of reproduction where bacteria
    replicate their DNA and divide in half producing
    2 new daughter cells.

19
  • Conjugation-
  • Exchange of genetic information through a hollow
    bridge like structure between two bacterial cells.

20
Pathogens
21
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