Kingdom MONERA Division EUBACTERIA CYANOBACTERIA - the

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Kingdom MONERADivision EUBACTERIACYANOBACT
ERIA - the Blue-Green Algae
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Some Characteristics of the Cyanobacteria
Contain Chlorophyll a and carotenoids, plus the
phycobilins (proteinaceous photosynthetic
pigments) phycocyanin and phycoerythrin (c f.
Rhodophyta), found in thylakoids Have cell
walls of peptidoglycan, often with a mucilaginous
sheath The carbohydrate stored is glycogen No
flagella, but some exhibit gliding movements
Some fix nitrogen in specialized cells called
heterocysts
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In some genera the mucilaginous sheath forms a
gelatinous matrix
Gelatinous matrix
Individual cells
Gloeocapsa
Filaments of Nostoc commune forming a gelatinous
ball
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Symbiotic Associations of Cyanobacteria
Anaboena azollae in leaves of the water fern
Azolla Nostoc in apogeotropic roots of Zamia
Nostoc and other genera in some lichens Nostoc
in leaves of some tropical angiosperms Richelia
in some pennate diatoms Nostoc in Anthoceros
(Hornworts) Gloeocapsa in polar bear hairs
Cyanelles in protozoans (Glaucophytes) -
cyanobacteria enclosed in vacuoles, and acting
like chloroplasts
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Apogeotropic roots and Anaboena nodules on Zamia
pumila
A - apogeotropic root H - hypocotyl P - primary
root
N - nitrogen-fixing nodule
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Cyanelles (endosymbiotic cyanobacteria) in the
glaucophyte Glaucocystis
Glucose is transferred directly to the host
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Heterocysts
In Anaboena, the heterocysts are intercalary
Oscillatoria lacks heterocysts
In Rivularia, the heterocysts are basal
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Akinetes
Heterocyst
Akinete
Cylindrospermum
Anaboena
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Cell and Filament Division in Cyanophyta
Cell Division in Anaboena
Hormogonium Formation in Oscillatoria
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False Branching in Cyanophyta
In Tolypothrix, false branching occurs adjacent
to the heterocyst
Scytonema
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Geological Activities of Cyanobacteria
Travertine (calcium carbonate) precipitated by
cyanobacteria in Yellowstone National Park hot
springs (from Moore)
Stromatolites forming on tidal flats in Western
Australia (from Raven)
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Cyanobacteria in Agriculture
The Water fern Azolla
Photo- synthetic tissue
Section through Azolla leaf
Cavity
Anaboena
Rice Paddy in Malaysia
Secretory hair
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Cyanobacteria as Food
Flamingoes feeding on Spirulina in alkaline Lake
Nakuru, Kenya
Spirulina contains 70 its dry weight as
protein Spirulina grows well in saline and
alkaline ponds in arid environments Native
peoples near Lake Chad (Africa) and Lake Texcoco
(Mexico) have traditionally used Spirulina as
food Spirulina is grown commercially in
California, Israel, Japan, Thailand Mexico