1. Day 3 - Blue-Green Bacteria Anabaena Gleocapsa Nostoc Oscillatoria

2. What are Blue-Green Bacteria?
aquatic
unicellular, but grow in colonies large enough to see
photosynthetic
oldest known fossils are 3.5 million years old

3. Where does the blue-green color come from?
get name from a bluish pigment: phycocyanin
also have chlorophyll a
reddish or pink strains have phycoerythrin

4. Importance of Blue-Green Bacteria
nitrogen fixation
first free oxygen
origin of plants
photosynthesis (primary producer in many ecosystems)
symbiotic relationships with legumes
endosymbiosis

5. What are we going to be doing?
Oscillatoria
Anabaena
Gleocapsa
Nostoc

6. Anabaena
single, straight chain of spherical cells (looks like a necklace)
heterocyst-forming
nitrogen fixation
anaerobic environment
Azolla

7. Gleocapsa
group of oval-shaped cells arranged within a mucus capsule (gelatinous sheath)

8. Oscillatoria
filaments made up of disc-shaped single cells; cells at ends of filament tapered or rounded
named for rotating motion around axis of filament
inhabits diverse environments
form dense, slimy mats of mud, plants, stones, or sand
can perform aoxygenic photosynthesis and release sulfur rather than oxygen

9. Nostoc
numerous coiled filaments of spherical cells which may comprise a visible globular (ball-shaped) mass looking like a squished grape
has a gelatinous sheath
heterocyst-forming
nitrogen fixation
anaerobic environment
abundant in rice paddies