Lab 1: Microorganisms in Activated Sludge Flashcards
(24 cards)
Bacteria
feeds on organic material
Protozoa
single-cell eukaryotic organisms that feeds on bacteria and organic material
Activated sludge
a type of biological wastewater treatment in which biological flocs consisting of bacteria and protozoa degrade organic materials in the presence of oxygen
When do amoeba show up
Start up conditions. Rarely a dominant group
when do flagellates show up
dominant if organic load is high
when do swimming ciliates show up
transition group that dominates between healthy and unhealthy conditions
when do Crawling ciliates show up
dominant if mature flocs are present and the biological oxygen demand is low (appears at same time as stalked ciliates)
when do stalked ciliates show up
dominant if mature flocs are present and the biological oxygen demand is low (appears at same time as crawling ciliates
what do rotifers signify
excellent sludge
why is sludge almost useless if flagellates are the dominant microorganism
the flagellates dont eat much
what do nematodes indicate in sludge
an almost useless sludge
amoeba features (5)
- no distinct shape
- move or feed using temporary body extrusions
- engulfed food is digested in food vacuole
- 800 um
- move extremely slow
pseudopods
amoeba’s temporary body extrusions that help them move or feed
Flagella features (3)
- 1 or more flagella for moving and sensing
- may be solitary, colonial or parasitic
- up to 50um
flagellum
movements of hair like structure and make whiplike lashing
Swimming ciliate features (3)
- hair like cilia that beat rhythmically to propel the organism through the liquid
- can be used to predict the quality of the plant’s effluent
- low number indicate a loading with toxic substances/organic overloading
effluent
liquid waste or sewage
Crawling ciliate features (1)
cilia look and function like legs and they crawl around on floc particles
Stalked ciliate
- usually attach themselves to floc or inert material, but can occasionally be seen moving through the water
- grow well when the bacterial population and dissolved oxygen concentrations are high
- heavily attached growth on the stalks indicate that the process is stable
Rotifer features (5)
- multicellular animal with differentiated tissue types
- 40 - 600um
- move by swimming or crawling
- exists in very stable activated slude
- stabalize organic waste, improves oxygen penetration into flox and recycle mineral nutrients
Rotifer major role
removal of filamentous bacteria in wastewater
cocci
round-shapes
bacilli
rod-shaped
spirilli
spiral shaped
