Environmental Science Week 2
Which LD50 score (dose in ppm) indicates the HIGHEST level of toxicity?
8
What did the comparative study on chytridiomycosis teach scientists studying white-nose syndrome in bats?
A novel fungal infection could spread to colonies and cause dramatic population crashes, as seen in the comparative study.
Which common logical fallacy is used when claiming there is no way to know the effect of lead, since humans are exposed to so many toxins; thus, we should do nothing about the use of lead?
Appeal to Ignorance
What is the difference between bioaccumulation and biomagnification?
Bioaccumulation is the buildup of substances within one organism, while biomagnification involves those substances moving up the food chain as one organism eats another.
You are a scientist doing research for U.S. Fish and Wildlife on the effect of fox predators on snowshoe hares. Park rangers have noticed fewer snowshoe hares in areas where foxes are more abundant. You set up two areas in the boreal forest with a fence that will allow the hares to get in but will keep out foxes, and two areas the same size that are marked but not fenced in. You count the number of snowshoe hares surviving after one year. The type of study you are setting up is a(n) _____ study.
Experimental
The Toxic Substances Control Act regulates _________________.
Industrial chemicals
Which statement is FALSE regarding a scientific theory?
It is an idea based only on observations
Cell theory states that all living organisms are made up of one or more cells. Which statement is FALSE regarding this theory?
No living organism will ever be discovered that is not made out of cells.
A researcher wants to know how effective a new suntan lotion is at preventing skin cancer caused by UV radiation. She uses mice as test subjects to model the effects on humans. Which statement describes the BEST control for this experiment?
No suntan lotion is applied to mice in the control group; lotion is applied only to the test group.
Which factor ensures that only quality scientific studies that have been well controlled and avoid bias appear in scientific journals?
Peer review
Which statement is NOT falsifiable?
People should not litter because it is wrong to do so.
Why is knowledge about the persistence of a chemical important when considering its toxicity?
Persistence measures how long a chemical remains in its present state in an area and, therefore, how long it might be a health concern.
Which hypothesis is NOT testable?
Reincarnation
You are out camping with friends. When you return home, you notice you have developed a rash on parts of your arms and legs. You have MOST likely come into contact with a:
Sensitizer
Why do scientists use comparative studies?
Similar phenomena in other species or regions can provide clues to events being investigated.
You are a scientist doing research for U.S. Fish and Wildlife on the effect of fox predators on snowshoe hares. Park rangers have noticed fewer snowshoe hares in areas where foxes are more abundant. You set up two areas in the boreal forest with a fence that will allow the hares to get in but will keep out foxes, and two areas the same size that are marked but not fenced in. You count the number of snowshoe hares surviving after one year. Which hypothesis is NOT testable in your experiment?
Something supernatural is decreasing the population of snowshoe hares.
Consumer groups called for a ban on BPA, a chemical known to be an endocrine disruptor, suggesting that financial interests from companies that profit from BPA-made products cause them to suppress data that might show BPA to be harmful. Which common logical fallacy is at work here?
ad hominen attack
Policies should address the triple bottom line—that is, they should:
address environmental problems, fit societal needs, and be economically viable.
In the following example, what is the independent variable? Hypothesis: Mice on a restricted low-caloric diet will live longer than mice that can eat as much as they want. Experiment: A large population of genetically identical mice is divided into two groups. Half receive as much food as they care to eat each day. The other half receive 20% less food than a typical mouse eats each day. The day of death (lifespan) is recorded for all mice. All mice live in the same room, in the same type of cage, with access to water.
amount of food available
Scientists are studying the effects of two chemicals on high blood pressure. When chemical A is used, blood pressure decreases by 20%. When chemical B is used, blood pressure decreases by 40%. When both chemical A and chemical B are used, blood pressure decreases by 35%. The effect of the chemical interaction is:
antagonistic
The __________________ effect of mercury means that it is not readily excreted (removed from body tissues); instead, it is stored in mammalian body tissues.
bioaccumulation
Chemical X was used widely in the United States as an insecticide for many years. Eventually, research showed chemical X was a persistent chemical that bioaccumulated and biomagnified in the environment. The chemical was later banned from use in the United States.
false dichotomy
In an experiment examining the effect of the Pd fungus on the torpor of bats, the presence of Pd fungus would be the _____ variable.
independent
In an experimental study, what is TRUE about the dependent variable?
it is a measured response
Which statement about lead exposure is FALSE?
lead is a fat soluble
Living on a fault line that is prone to earthquakes is an example of a ________________.
physical hazard
The lead found in the water in Flint, Michigan, is what type of toxic chemical?
poison
Which information source is peer reviewed?
primary
Which example is NOT a part of critical thinking?
refusing to believe anything
According to the Precautionary Principle, we should ______________.
restrict any chemical that is suspected of toxicity until it is proven safe
Nicotine and alcohol have been shown to be harmful to a fetus in the womb because they can lead to birth defects. Nicotine and alcohol are, therefore, potential ____________.
teratogens
Which type of source is the MOST likely to perpetuate errors that have previously appeared?
tertiary
Which question can be solved with empirical evidence?
what causes the season change
