Transcript Bacteria and Algae

Bacteria and Algae
Chapters 6-7
Marine bacteria
• Small, prokaryotic cells
• Reproduce asexually via binary fission
• 3 forms
– Chemosynthetic
– Photosynthetic
– Heterotrophic
Photosynthetic bacteria
• Makes food from light energy
• Cyanobacteria (blue-green algae)
– Most common type of photosynthetic algae
– Single cells or long chains
– Pump free oxygen back into the water
Photosynthetic Bacteria
• Stromatolites
– Dense mats of blue green algae that traps
other organic material
– Believed to be dominant in prehistoric times
Chemosynthetic Bacteria
• Makes food from chemical energy
• Use Carbon Dioxide and sulfur or
ammonium
• Found deep in the sea where sunlight is
non-existent
Heterotrophic bacteria
• Decomposers in the ocean floor
– Have the ability to break down tough organic
molecules such as chitin, cellulose, lignin, and
keretin
– Recycles materials to be used by primary
producers
Symbiotic Bacteria
• Chemosynthetic bacteria of hydrothermal
vents produce chemicals that sustain deep
sea communities
• Bacteria living in deep sea organisms
provide bioluminescence
Other Microscopic Organisms
• All other microscopic organisms are
eukaryotic
• More complex than bacteria
• Provide similar services
Diatoms
• Cells surrounded by a frustule
– Frustule- 2 part silica based “box”
– Box expands at the union as the cell inside
grows
• Frustules do not decompose
– Fall to ocean bottom
– Uplifted to Create diatomaceous earth
Diatomaceous Earth Uses
• Filtration
– Pool filters, alcohol filters
• Polishing abrasive
– Toothpaste
– Silver polish
• Sound proofing and Insulation
Multicellular algae
(seaweeds or macroalgae)
• Highly influenced by light patterns
• Includes Green Algae, Red Algae, and
Brown algae
• More diverse in warmer waters
Structure of Seaweeds
• Thallus- Main body of seaweed
– No leaves or roots, as they are non-vascular
– All cells of thallus photosynthesize
• Photosynthetic pigments
– Chlorphylls a-d
– Accessory pigments may absorb other lights
to pass on to chlorophylls, giving different
colored seaweeds (reds and browns)