Transcript cyanobacteria - Sumber Belajar









CIRI-CIRI UMUM:
-Tipe sel: sel Prokariotik (sama dengan bakteri)
-Uniseluler dan Multiseluler
-Memiliki pigmen fikosianin
-Klorofil tidak di dalam kloroplas, tetapi tersebar di
seluruh sitoplasma
HABITAT
-Perairan (terutama perairan tawar) dan tempattempat lembab.
-Mampu hidup pada perairan dengan suhu sampai
85 derajat C (sumber air panas) sehingga
Ganggang Biru merupakan salah satu vegetasi
perintis.
1. Alga biru uniseluler
- Chroococcus -> hidup di air/kolam yang
tenang
- Gloeocapsa -> hidup pada batu atau epifit pada
tumbuhan lain
2. Alga biru uniseluler berkoloni
- Polycistis
- Spirulina -> dapat diolah menjadi makanan
kesehatan (food suplement)
3. Alga biru berbentuk benang
- Oscillatoria
- Nostoc commune
- anabaena azollae dan anabaena cycadae
bersimbiosis dengan Azolla pinnata dan Cycas
rumphii. Simbiosis Anabaena azollae dengan
Azolla pinnata sebagai alternatif pupuk Urea,
karena simbiosis ini dapat meningkatkan kadar
Nitrogen di lahan persawahan.

Cyanobacteria
Figure 16.13x

These bacteria photosynthesize in a plant-like
way
◦ They often “bloom” in polluted water
Figure 16.13A, B
Some Characteristics of the Cyanobacteria
• Contain Chlorophyll-a and carotenoids, plus the
phycobilins (proteinaceous photosynthetic
pigments) phycocyanin and phycoerythrin found
in thylakoids
• Have cell walls of peptidoglycan
• The carbohydrate stored is glycogen
• Don’t have flagella
• Some fix nitrogen in specialized cells called
heterocysts
Gelatinous
matrix
Individual
cells
Gloeocapsa
Filaments of
Nostoc commune
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
Cyanelles (endosymbiotic cyanobacteria) in the ‘glaucophyte’
Glaucocystis
Heterocysts
In Rivularia, the
heterocysts are
basal
In Anaboena, the
heterocysts are
intercalary
Oscillatoria lacks
heterocysts
Akinetes
Heterocyst
Akinete
Cylindrospermum
Anabaena
Cell and Filament Division in Cyanophyta
Cell Division in Anaboena
Hormogonium Formation
in Oscillatoria
False Branching in Cyanophyta
In Tolypothrix, false
branching occurs adjacent to
the heterocyst
Scytonema
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)
Cyanobacteria in Agriculture
The Water fern Azolla
Photosynthetic
tissue
Rice Paddy in Malaysia
Section
through
Azolla
leaf
Cavity
Anaboena
Secretory
hair
Cyanobacteria as Food
Flamingoes feeding on Spirulina
in alkaline Lake Nakuru, Kenya
* Spirulina contains 70% its dry weight as protein
* used Spirulina as food (Single cell Protein)