apes unit 7 test limnology
the LD-50 for arsenic humans is 13/mg/kg. which of the following should be used to determine the number of grams for a 140 pound person?
140lbx2.2/1x1/13x1/1000
what is the LD-50 sample shown in the graph
22 mg
which is the benthic zone?
3
which of the following is likely to be leached from old pipes if the water is too corrosive?
lead
which of the following is measured to determine the clarity of water?
turbidity
which best describes thermal pollution?
warm water released from power plants that decrease DO in water
what law is most likely to deal directly with this site?
CERCLA
which of the following best explains why DDT has been found in penguin eggs in the antarctic?
Chemicals used in one region of Earth can circulate in the biosphere and affect organisms in a distant region.
what chemical was famously banned due to the reproductive issues in eagles?
DDT
which of the following best describes why DDT is classified as a persistent organic pollutant?
DDT is very stable, and as much as 50% of the original concentration
Poses a health risk to humans who eat large quantities of marine fish such as swordfish and tuna.
Mercury
which of the following is the largest aquifer in the US?
Ogallala
which of the following is the best example of a point source pollutant?
Oil tanker spill
A scientist is studying PCBs in teritary consumers. she wants to determine if PCBS teri start consumers even though they were banned in the US. which of the following best identifies a testable hypothesis for this experiment?
PCBS are persistent organic compounds that are fat soluble, so they should be found in the fatty tissues of consumers.
A point source discharges organic waste into a stream. Which of the following graphs best depicts the expected pattern for dissolved oxygen (DO) in this stream as a function of distance from the discharge point?
a (slight curve/downwards)
which of the following is a correct example of the term "riparian buffer"?
an area with vegetation surrounding channel to reduce runoff
which of the following is likely result from destruction surrounding a river?
an increased frequency of flooding in a river
Eutrophication results in the death of trout and other fish though
asphyxiation from lack of oxygen
regulates the release of potentially hazardous chemicals into bodies of water?
clean water act
A point source discharges organic waste into a stream. What is the name given to expected patterns for dissolved oxygen?
discharge point curve
name one other disease that can be spread through similar methods of cholera
dysentery
puffins that like to hang on an island with higher levels of dioxins had low levels of testosterone and weren't able to reproduce because
endocrine disruptors
Which type of lake has the largest amount of nutrients?
eutrophic
which of the following water quality tests would be the best to indicate if sewage from the wastewater treatment plant has contaminated moose water?
fecal coliform measured at site b
A research team monitoring a local freshwater ecosystem noticed that over the past few years the otter population had declined significantly, while the populations of other species remained fairly constant. After running tests, the research team determined that mercury levels in invertebrates and small fish in the ecosystem were very high. In this ecosystem, what role did the otters occupy?
indicator species
which of the following is not an effect of sediment pollution?
lowered capacity for dissolved oxygen
the over harvesting of peat moss use in gardening is most likely to damage which of the following ecosystems?
marsh
which of the following is the most reliable way to determine if a stream has consistently healthy parameters?
observing using the visible features
which species would be better suited as an indicators species for the health of a forest ecosystem?
opossums that only way dead things
all of the following are considered a toxic metal pollutant except
potassium
after a major hurricane, drinking water may become contaminated and residents may have to import bottled water. which kind of law determines where the safe cut off is for this situation?
safe drinking water act
the excessive pumping of groundwater from wells can influence the water levels below ground. which of the following is more likely to occur in aquifers in coastal areas than regions?
saltwater intrusion into the aquifers
Many synthetic chemicals, such as PCBs, act as estrogen mimics. In an ecosystem, these persistent chemicals would have the greatest effect on which of the following?
secondary consumers
at which step in wastewater treatment aeration takes place?
secondary treatment
which of these components is removed in a primary clarifier during waste water treatment?
small particles of dirt
due to the toxic substances at this location, what would the classification of this site likely be?
superfund site
based on the diagram above, which of the following best describes why a population in an area that has poor sanitation be at risk for cholera outbreak?
the bacterium that causes cholera is spread through contamination of ingested water and food
which of the following should be included in a watershed map to best determine the non source point pollutant in a river?
the land use upstream of a river and the water quality indicators in streams that run downstream into the river
which of the following is an environmental problem associated with coal mines
thermal pollution of streams in the area