Lab Flashcards
(104 cards)
Freshwater aquatic representatives of phylum Arthropoda are….?
Crustaceans, insects, Arachnids
List some generalities of the Protozoa
Eukaryotes, all single celled, sometime colonial, usually live in aquatic environments, they are highly tolerant of extreme conditions
What are the groups found in freshwater ecosystems within class Branchiopoda
Fairy shrimps (cladocerans) and clam shrimps (conchostracans)
Daphnia is a _______ within the class _______
Conchostracan, branchiopoda
What is “nitrifying”?
Bacterial conversion of ammonia to nitrite or nitrite to nitrate.
What happens when water containing ammonia is chlorinated?
All ammonia must be oxidized before chlorine can actually help purify water. Chlorine and ammonia react to create monochloramines and dichloramines
How do nitrate and nitrite affect human health?
Nitrate is converted to nitrite by the human gastrointestinal tract. Excess nitrite is associated with methemoglobinemia in infants, birth defects, developmental problems of the central nervous system. Nitrite can also influence gastric cancer.
What are the Canadian guidelines for nitrate in water?
45mg/L nitrate or 10mg/L nitrate-N
How are nitrate levels measured in water?
Ultraviolet spectrophotometry or nitrate electrode
How does phosphorous influence natural waters?
Is primary nutrient determining trophic state of lake.
What amount of inorganic phosphorous indicates eutrophic status
0.02mg/L
In what forms is phosphorous found in natural waters
Primarily phosphates. Orthophosphates, condensed phosphates (such as pyrophosphates or metaphosphates) and organic phosphorous compounds. Found in water, detritus, or living organisms. `
What type of organism is this?

Euglena
What are the defining features of the protazoa?
Eukaryotic. Usually single-celled (some colonial), can be anywhere from 5 micrometers to 5mm long. Most are quatic, but some are parasitic.
Describe freshwater protozoa
Very small (nanoplankton). Highly tolerant of extreme conditions. They feed on bacteria, small phytoplankton and other protozoa. Some ingest dead organic matter and play a large role in nutrient cycling. Most dislike bright light.
Describe the class Rhizopoda
Contain amoeboid protozoa that use pseudopodia for locomotion and feeding. Cells may be completely naked, often multinucleate. Others may have loosely fitting external shells called tests.
Describe Rhizopodan “tests”
Composed of proteinaceous matrix which can be either silica scales or sand grains. Pseuodopodia emerge from openings in the test. Tests can also contain a bubble of gas for buoyancy
Describe amoeba
Move with pseudopodia. Phagocytize bacteria and other micro organisms. Can produce dormant cysts that withstand freezing/dessication.
What kind of organism is this?

Amoeba
To what phylum does this organism belong?

Rhizopoda
To what phylum do these organisms belong?

Actinopoda
_______ is the largest protozoan phylum
Ciliophora
Describe the structure of organisms in the group actinopoda
May be naked or have a silicaceous skeleton with scales/spines. Have thin pseudopods called “actinopodia” as well as delicate filopodia that radiate from the internal skeleton. They feed on other protozoa or on very small multicellular animals.












































