BIOL 112 Lab 3

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Objectives:

• Describe characteristics of 3 domains
• Differentiate between aerobic, anaerobic, and acultative anaerobic bacteria
• Describe 3 vital contributions bacteria make to the global ecosystem
• Identify two ways bacteria obtain energy
• Differentiate cyanobacteria from other types of bacteria
• Describe protistan diversity
• Use distinguishing characteristics to develop a cladogram of representatve protistans

Single-Celled Organisms

Three Domains:

1. Bacteria
2. Archaea
3. Eukarya

(1) and (2) are prokaryotes (lack membrane-bound organelles and nuclei)

Ecological Importance of Bacteria

Contributions to ecosystems:

• Digestion aid
• Nitrogen fixation
• Oxygen production
• Decomposition of organic materials

We use them for:

• Genetic engineering
• Sewage treatment
• Cleaning up toxins
• Producing antibiotics^?
• Foods such as yogurt and cheese

Classification in response to atmospheric oxygen:

• Aerobic require oxygen for growth
• Anaerobic cannot tolerate oxygen
• Facultative anaerobes tolerate oxygen, but can survive without it

Single Celled Organisms

• Domain Archaea
  • Halophiles (salt-loving)
  • Thermoacidophiles (heat/acid-loving)
  • Methanogens (methane-eaters)
• Domain Bacteria
  • Cyanobacteria
• Domain Eukarya (formely known as protists)
  • Supergroup Excavata
    • Group Diplomonadida (e.g. giardia intestinal parasite)
    • Group Parabasala (e.g. Trichomonas vaginalis STD)
    • Group Euglenozoa
      • Subgroup Euglenids (e.g. Euglena)
      • Subgroup Kinetoplastids (e.g. Trypanosoma African sleeping sickness)
  • Supergroup Chromalveolata
    • Group Alveolata
      • Subgroup Dinoflagellates (spinning basketballs)
      • Subgroup Apicomplexans (e.g. Plasmodium vivax malaria)
      • Subgroup Ciliates (e.g. Paramecium)
    • Group Stramenopila
      • Subgroup Oomycetes (water mold; potato blight)
      • Subgroup Bacillariophytes (e.g. diatoms)
  • Supergroup Rhizaria
    • Group Foraminifera ("forest" tests of CaCO₃)
    • Group Radiolaria ("radially symmetric radio speakers" of silica)
  • Supergroup Unikonta
    • Group Amoebozoa (e.g. amoeba)