Building Blocks of Life

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Diversity of Life
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Diversity of Life
Kingdom
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Diversity of Life
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Viruses

• Not a living organism
• Parasite uses other organisms to replicate
• Infect all organisms, particularly bacteria
• 10 million/ml in ocean

http//oceanworld.tamu.edu/resources/oceanography-
book/Images/BacteriophageCartoon.jpg
http//www.eoearth.org/image/Infected_cell.jpg
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Prokaryotes

• Domain Archaea
• Domain Bacteria
• Structurally simple, lack most organelles
• Mostly microscopic
• Circular DNA

http//www.windows.ucar.edu/earth/Life/images/cell
types.gif
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Eukaryotes

• 1 Domain Eukarya
• 4 Kingdoms Protista, Plantae, Fungi, and
  Animalia
• Structurally complex
• Have membrane-bound organelles with specialized
  jobs
• Mitochondria and chloroplasts organelles that
  were once symbiotic bacteria

http//www.windows.ucar.edu/earth/Life/images/cell
types.gif
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Diversity of Life - Archaea

• Simple, primitive
• Old (3.8 billion years)
• Recently discovered (1970s)
• Look like bacteria, but chemically different

http//www.ucmp.berkeley.edu/archaea/archaeamm.htm
l
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Diversity of Life - Archaea

• Have reputation as extremophiles
• Found almost everywhere
• Very common in oceans

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Diversity of Life - Archaea

• Extreme high and low temperatures areas
  (thermophiles)
• Volcanic hot springs, hydrothermal vents

Archaea Strain 121 survives up to
121C, reduces iron into byproduct magnetite
http//www.nsf.gov/od/lpa/news/03/pr0384.htm
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Diversity of Life - Archaea

• Extreme salty regions (halophiles)
• Hypersaline lakes
• Salinity 300 or more

Haloquadratum walsbyi
http//www.espacial.org/images/jpg2/haloquadratum_
walsbyi.jpg
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Diversity of Life - Archaea

• Extreme alkaline and acidic areas
• Extreme pressure - deep trenches
• Anoxic muds

Picrophilus torridus lives at 60C and pH0
Archaea in acid mine drainage
http//microbewiki.kenyon.edu/images/4/4f/Picrophi
lus_torridus.jpg
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Diversity of Life - Archaea

• Symbiotic associations with other organisms
• Methanogens live in digestive guts of plankton,
  sea cucumbers
• Others still being discovered

green archaeum (Cenarchaeum symbiosium) red
red sponge (Axinella mexicana) cell nuclei
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Diversity of Life - Bacteria

• Simple, old
• Variety of shapes and sizes

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Diversity of Life - Bacteria

• Found almost everywhere (including extreme
  environments)
• Found in huge quantities in the ocean

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Diversity of Life - Bacteria

• Important part of nutrient recycling
• Decomposition of organic matter (dead, wastes)
• Food for other organisms

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Diversity of Life - Bacteria

• Cyanobacteria (blue-green algae)
• Green, blue, and red photosynthetic pigments
• First photosynthetic organisms on earth
• Stromatolites (3 bya and today) calcareous
  (CaCO3)

http//web.eps.utk.edu/HistoricalGeo/historicalima
ges/Stromatolite.jpg
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Diversity of Life - Bacteria

• Symbiotic associations with other organisms
• Chemosynthesis in tube worms, mussels, clams at
  hydrothermal vents and cold seeps

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Diversity of Life - Bacteria

• Symbiotic associations with other organisms
• Digestive gut bacteria (shipworms, bone worms)

http//www.phschool.com/science/science_news/artic
les/images/gutless_wonder.jpg
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Diversity of Life - Bacteria

• Symbiotic associations with other organisms
• Bioluminescence in squid, fish
• Vibrio, Photobacterium

http//microbewiki.kenyon.edu/images/c/c9/Vibrio_f
ischeri_1145457864.jpg
http//www.divernetxtra.com/biolog/pics/0900flash1
.jpg
http//beacon-center.org/wp-content/uploads/2012/0
3/lumflaskmod1.jpg
http//www.pbs.org/wgbh/nova/abyss/life/images/wud
ep50.jpeg
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Diversity of Life Metabolism

• Organisms that can make own food autotrophs
  (self feeders)
• Organisms that must eat other organisms or
  organic matter for food heterotrophs

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Diversity of Life Metabolism

• 7 different types of pathways possible
• 4 heterotrophic
• Aerobic respiration
• Anaerobic respiration
• Nitrogen fixation
• Anaerobic ammonium oxidation
• 3 autotrophic
• Light-mediated ATP synthesis
• Photosynthesis
• Chemosynthesis

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Diversity of Life Metabolism

• Aerobic respiration, uses oxygen (O2), burns
  organic matter to get energy
• Prokaryotes and eukaryotes
• Decomposition of organic matter

C6H12O6 O2 ? CO2 H2O energy (sugar)
(ATP)
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Diversity of Life Metabolism

• Anaerobic respiration, uses NO3-, SO4-2, or CO2
  instead of O2
• Nitrogen fixation
• Makes nitrogen gas (N2) usable to organisms as
  ammonia
• Anaerobic ammonium oxidation
• All of these 3 require anoxic conditions
• All of these 3 are in prokaryotes only

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Diversity of Life Metabolism

• Light-mediated ATP synthesis - prokaryotes only
• Photosynthesis
• Prokaryotes and
• eukaryotes (only algae
• and plants)
• Need chlorophyll and
• other pigments
• Converts inorganic
• carbon to organic
• Photoautotrophs

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Diversity of Life Metabolism
Photosynthesis
CO2 H2O light ? C6H12O6 O2 energy
(sugar)
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Diversity of Life Metabolism

• Chemosynthesis
• Energy from chemicals (H2S), not light
• Critical for life at hot and cold seeps
• Prokaryotes only
• Chemoautotrophs

http//oregonstate.edu/dept/ncs/photos/grazers.jpg
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Diversity of Life Metabolism

• Autotrophs must also use respiration to get ATP
  energy

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Diversity of Life Metabolism

• 7 classes of metabolic reactions possible in
  prokaryotes
• Only 2 in eukaryotes (photosynthesis, aerobic
  respiration)

http//www.addletters.com/Godzillatron-football-si
gn-generator.htm
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Prokaryotes vs. Eukaryotes
Prokaryotes Eukaryotes
Domains/ Kingdoms Bacteria, Archaea Animalia, Plantae, Fungi, Protista
Cellular Complexity Simple Complex, organelles
DNA structure Simple, circular Chromosomes in a nucleus
Cellular Organization All unicellular Some unicellular, many multicellular
Metabolic pathways Variety, 7 possible Only 2 aerobic respiration photosynthesis
Feeding strategy Auto heterotrophy Auto heterotrophy