Prokaryotes – Bacteria and Archea No membrane bound organelles Large surface area to volume ratio Asexual reproduction by binary fusion Single celled or.

Prokaryotes – Bacteria and Archea

No membrane bound organelles

Large surface area to volume ratio

Asexual reproduction by binary fusion

Single celled or colonial

Anaerobic metabolism – what’s going on in the hypolimnion of a stratified, anoxic lake?

Chemoheterotrophs and Photohetertrophs – using active transport, more efficient at low nutrient concentrations

Photoautotrophs – i.e. cyanobacteria (blue-green algae)

Ecology

Diapause – it may be that the dormancy is very important in bacteria

Cyanobacteria

Prokaryotes (no nucleus or organelles)Blue-greenPigment = Chl a

Filamentous blue-green algae (Cyanophyta)

Protista – Protozoa and algae

Eukaryotic (membrane bound organelles, nucleus, mitochondria, chloroplasts in photosynthetic protists)

Single celled (although may be colonial)

Protozoa

Also Giardia and Cryptosporidium

Heterotrophic Protists

Paramecium, amoebas, Euglena, Hydra

Photoautotrophic Protista – Algae

Single celled or colonial

Floating

Phytoplankton

Benthic algae

Attached to surfaces (rocks, sediment)

Chlorophyta - Green

Green-yellow greenPigment = Chl a and bSome have flagella

Chrysophyta

Yellow green to golden brownPigment = Chl a and cSome have 2 flagella

Chrysophyta (Golden-brown algae) Diatoms

Brown to light greenPigment = Chl a and cSome have flagellaSilica walls – composed of 2 frustules

Euglenophyta

Pigment = Chl a and bAll have flagellaEyespotsMost are heterotrophic and autotrophic

DinoflagellataGrayPigment = Chl a and cTwo flagellaSome are highly toxic

Pfisteria

Reproduction - diverse

Vegetative cell

resistant cell (resting stage)

Encystment

Germination

Asexual reproduction

usually binary fission

Sexual reproduction – possibly motile gametes or conjugation tubes

Fungi

Yeasts

Hyphae grouped into mycellium

Chemoautotrophs (saprobic)

Sexual and asexual reproduction

Ecological importance

Breakdown of detritous

Parasites on other aquatic organisms

Periphyton (or aufwuchs) – pond scum

A community of algae, fungi, bacteria