1. Animal rights groups often target the LD50 standard as an example of callous indifference to animal welfare. Other groups argue that standards such as LD50 are necessary to ensure drug safety and effectiveness. Take a position on the issue and write a letter to the editor of a newspaper defending your position.
2. During a lifetime, you will eat a prodigious amount of food, estimated to be about 700 times your adult body weight. This statement is itself quite a prodigious assertion. Do calculations to check that the statement is in the ballpark. State all of your assumptions clearly.
Hint: Start by assuming a lifespan of approx. 78 years and that you present weight is 160 pounds. Estimate the weight of food eaten daily at present, and use these data to project your lifespan consumption of food.
3. Sometimes authors get carried away with their rhetoric. Check the correctness of the claim that the DNA in an adult human being would stretch from the Earth to the Sun over 60 times. It is approx. 93 million miles from the Earth to the Sun.
Note: You contain about 10 million million (10 X 10 to the 12th power) cells that have a nucleus. The genetic instruction is organized in 23 pairs of chromosomes approx. 100,000 genes, each of which conveys one or more hereditary traits (human genome). If all of the DNA in all 10 million million of your cells were placed end to end, the resulting ribbon would stretch from here to the Sun more than 60 times.
For question 1, the main question is, "What substantiates callous indifference to animal life?" It would be my position that animal rights groups are more callous in their position that these tests should be abolished or somehow made less severe. I would not choose to argue on the front of animal versus human life since these tests support all animal life in the earth's environment.
However, one can make a case that a standard such as LD1 or LD25 even would serve the same purpose (and these standards are in fact used as well), the argument being that if a chemical kills one percent of a population at a particular dosage, there is no need to increase the dosage, because certainly it will be more fatal. This argument is fallacious at several levels, too complex to address in a letter to the editor. But the argument is real
nonetheless and made several times over. It would not be specious to pursue this line of reasoning if it were followed carefully.
Ultimately it will be your decision which case to argue, but I argue mine below, in letter format. I respectfully request that you use the essay below for reference only and as an example of a letter that might be compelling for a nonscientific audience. Best of luck in fashioning a factual and careful argument on this ...
The expert response provides a written letter holding the position that medical animal testing is acceptable as well as explanations on how to complete the additional questions of estimation calculations.