Cyanobacteria

Outline

Introduction

prokaryotic autotrophs

diversity

Morphology and reproduction

unicellular -- binary fission of cells

colonial -- fragmentation

filamentous -- sometimes by means of hormogonia

Ecology

aquatic

planktonic

periphytic

terrestrial

wet soils

tree bark

etc.

special habitats

Cell structure

basic prokaryotic features

the outer layers

mucilaginous sheath

cell wall

cell membrane

cytoplasm

ribosomes

nuclear material

features that allow photosynthesis

thylakoids -- morphology and arrangement

pigments

chlorophyll a

carotenoids -- beta carotene

phycobilins

phycoerythrin and phycocyanin

in phycobilisomes

reserve materials (storage products)

cyanophycean starch

cyanophycin granules

polyphosphate granules

carboxysomes

special features

gas vesicles

Special cells

heterocysts -- solving the problem of nitrogen fixation in an oxygen-rich environment

akinetes -- resting cells

Importance

historical

ecological

economic

Prochlorophytes

photosynthetic prokaryotes

• chl a and b
• stacked thylakoids
• no phycobilins

polyphyletic

Vocabulary

click here to go to Cyanobacteria vocabulary