Transcript Document

Blue-Green Bacteria
Day 2
Welcome to Class
Please take out your
notebook.
Be ready to write.
Blue green
algae have
cells walls
similar to
eubacteria
Blue Green Algae?
Blue Green Pigment
(Phycocyanin and Chlorophyll)
No Membrane bound Organelles
(No Nucleus)
Single cell but form colonies
Perform Photosynthesis
• Question: Algae or Bacteria?
What is blue-green bacteria?
• A phylum of bacteria
• Gets energy through photosynthesis
• Found everywhere (hotsprings, artic,
antartica)
• Can live as one cell or in colonies,
filaments, sheets or hollow balls
Nostoc Colony “Star Jelly”
What are some cell types of
blue green bacteria?
• Normal cells
• Cells with resistant spores (akinetes)
• Thick walled cells for fixing nitrogen
(heteocysts)
What are some parts of bluegreen bacteria
• Thick, gelatin cell wall
• No flagella
• How do they reproduce? Hormogonia
are filaments that glide away from the
main mass, bud, and reproduce.
Global Importance of Bacteria
Diverse Bacteria
• Nitrogen Fixers: Heterocysts aid in nitrogen
fixation. To "fix" nitrogen gas, means to change
nitrogen which cannot be absorbed by plants,
into ammonia (NH3), nitrites(NO2) or nitrates
(NO3), which can be absorbed by plants and
converted to protein and nucleic acids)
• Photosynthesis
Anabaena
• look like chains of tiny grapes
• can fix its own nitrogen
• produces a chemical that is
toxic to many species of
animals.
• similar to Nostoc, except
large balls are not normally
formed. Cells more elongate,
less rounded.
Spirogyra
• From Greek speira, "coil" +
gyros, "twisted"
• Most diverse of the conjugating
green algae,
• Almost half of these can be
found in North America.
• Shape: The genus usually
exists as loose, floating mats,
• Forms extensive but harmless
springtime blooms in
freshwater ponds.
• http://video.conncoll.ed
u/f/pasiv/lucid/Spirogyra
-900.html
Oscillatoria
• Very common.
• ShapeWell defined unbranched
filaments (simple or
interwoven into dense mat)
Reproduction fragmentation at
separation discs;
Nostoc
• Occurs in soil and in fresh-water
Form:
• Twisted trichomes with individual
sheath, often aggregated into
large gelatinous balls.
• Heterocysts present, fragment
here. Akinetes formed when
colony matures.
• Nostoc Often associated with
fungi in lichens, filamentous, can
form colonies, akinetes midway
between heterocysts.