Q: I read this background article the other day: Currently, millions of individuals with high cholesterol take a similar type of drug, known as a statin. The drug, an inhibitor of HMG-CoA reductase (3-hydroxy-3-methyl-glutaryl-CoA reductase), the rate limiting enzyme in cholesterol biosynthesis, decreases blood levels of cholesterol by induce the expression of low density lipoprotein (LDL) receptors in the liver. The increased levels of the LDL-receptors stimulate the catabolism of plasma LDL, removing cholesterol from plasma, which is an important determinant of atherosclerosis. You may know of people who take a statin to help with their cholesterol levels. However, these drugs probably work slightly differently in many of those people. In some, it lowers their cholesterol significantly; in others it may lower it only moderately; and in some, it may have no significant effect at all. (Luckily for those individuals, there are multiple versions of the statins, so different drugs can be tested to find the proper combination for that individual.) Why the difference? Because of the genetic background of all people; the different single nucleotide polymorphisms that make us all different. Pharmacogenomics, a combination of pharmacology and genomics (the study of the genome) that refers to the study of the relationship between pharmaceuticals and genetics, may explain and simplify this problem. I am facing a new situation today: Ben and Andy were two old friends. They both have high levels of cholesterol. Ben was prescribed cholesterol medication, while Andy didn't go to the doctor because he was careless. Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Which friend took a drug that induces the expression of low density lipoprotein (LDL) receptors in the liver?
A: Ben

Q: I read this background article the other day: One result of air pollution is acid rain. Acid rain is precipitation with a low (acidic) pH. This rain can be very destructive to wildlife. When acid rain falls in forests, freshwater habitats, or soils, it can kill insects and aquatic life. It causes this damage because of its very low pH. Sulfur oxides and nitrogen oxides in the air both cause acid rain to form ( Figure below ). Sulfur oxides are chemicals that are released from coal-fired power plants. Nitrogen oxides are released from motor vehicle exhaust. I am facing a new situation today: The ecologist moved from Aspen, where there was no air pollution, to Seattle which experienced a lot of air pollution. He started studying the weather there as well. Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Which city had rain with a lower pH?
A: Seattle

Q: I read this background article the other day: Einstein showed in his thought experiments that people travelling at different speeds, while agreeing on cause and effect, measure different time separations between events, and can even observe different chronological orderings between non-causally related events. Though these effects are typically minute in the human experience, the effect becomes much more pronounced for objects moving at speeds approaching the speed of light. Subatomic particles exist for a well known average fraction of a second in a lab relatively at rest, but when travelling close to the speed of light they are measured to travel farther and exist for much longer than when at rest. According to the special theory of relativity, in the high-speed particle's frame of reference, it exists, on the average, for a standard amount of time known as its mean lifetime, and the distance it travels in that time is zero, because its velocity is zero. Relative to a frame of reference at rest, time seems to "slow down" for the particle. Relative to the high-speed particle, distances seem to shorten. Einstein showed how both temporal and spatial dimensions can be altered (or "warped") by high-speed motion. I am facing a new situation today: David wanted to test the theory of Einstein. To that end, he measured the time perceived by an airline pilot, who naturally traveled very fast. He labeled it as case A. To compare the pilot with a slower traveler he measured the time perceived by a semi truck driver covering the same distance. He labeled it as case B. He was amazed by the counter intuitive results he got from the experiment. Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: According to Einstein, who would perceive the distance as longer, case A or case B?
A: case B

Q: I read this background article the other day: Ocean acidification occurs when excess carbon dioxide in the atmosphere causes the oceans to become acidic. Burning fossil fuels has led to an increase in carbon dioxide in the atmosphere. This carbon dioxide is then absorbed by the oceans, which lowers the pH of the water. Ocean acidification can kill corals and shellfish. It may also cause marine organisms to reproduce less, which could harm other organisms in the food chain. As a result, there also may be fewer marine organisms for humans to consume. I am facing a new situation today: Two islands were situated in different oceans. Hill island used fossil fuels and released a lot of carbon dioxide into the atmosphere, while Coral island was very protective towards the air and the ocean. Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Which island contributed more to the death of corals?
A:
Hill