Environmental Science Standards Mastery Sheet SC.912.N.1.2: Describe and explain what characterizes science and its methods. Question #1: Jacqueline is interested in helping her overweight cat lose weight so that he will be healthier and more active. She selects a new cat food based on the label’s claim that it can help with weight loss. Jacqueline measures out the food carefully each day, has been weighing the cat every 48 hours, and records the measurement. What keeps this practice from being a scientific experiment? A. B. C. D. There is only one cat and one type of food being used. The cat should be weighed every day to collect more data. She has not considered whether the cat will like the new food. The food is not the brand that Jacqueline’s friend used for his overweight cat. Question #2: Justin wants to test different water filters to see which ones yield samples with the least ions (charged particles) in the filtered product. He borrows a hand-held instrument that can make these measurements and sets up his procedure. Justin purchases new filters with similar water volume capacities, uses the same amount of water from different faucets, and tests triple samples from each water source. What is the independent variable for this experiment? A. B. C. D. the time needed for filtration the type of filters used for testing the volume of water collected during filtration the amount of ions found in the filtered water Question #3 A company has investigated a new pesticide that it is advertising as being biodegradable and safe for using on food crops. The research work was done by a scientist who is employed by the same company which produces the pesticide, and the company is anxious to start marketing and selling the pesticide. Which of the following issues is the most troubling scientifically? A. The researcher has not gotten a patent to protect the design of the pesticide. B. The information has already been presented at trade conferences to salespeople and CEOs. C. The research has been reviewed by outside scientists who have financial investments in similar products. D. As a company employee, the researcher may have been biased when interpreting the experimental data. Environmental Science Standards Mastery Sheet - Answer Justification Question #1: Jacqueline is interested in helping her overweight cat lose weight so that he will be healthier and more active. She selects a new cat food based on the label’s claim that it can help with weight loss. Jacqueline measures out the food carefully each day, has been weighing the cat every 48 hours, and records the measurement. What keeps this practice from being a scientific experiment? A. B. C. D. There is only one cat and one type of food being used. The cat should be weighed every day to collect more data. She has not considered whether the cat will like the new food. The food is not the brand that Jacqueline’s friend used for his overweight cat. A is the correct answer since the use of one animal and one type of food does not provide multiple trials or proper controls. B is incorrect since weight loss would be an experiment that could take weeks to see changes, so daily measurements are not essential. The cat’s response to the food or the food used by someone else are not factors that interfere with scientific principles, so neither C nor D are correct. Question #2: Justin wants to test different water filters to see which ones yield samples with the least ions (charged particles) in the filtered product. He borrows a hand-held instrument that can make these measurements and sets up his procedure. Justin purchases new filters with similar water volume capacities, uses the same amount of water from different faucets, and tests triple samples from each water source. What is the independent variable for this experiment? A. the time needed for filtration B. the type of filters used for testing C. the volume of water collected during filtration D. the amount of ions found in the filtered water B is the correct answer since it describes an independent variable that supports Justin’s hypothesis, although he could choose alternatives not listed such as the faucet source. A is incorrect since time is not directly related to ion concentration. C is incorrect since water volume is being controlled and is not a variable. D is incorrect since it is the dependent variable. Question #3 A company has investigated a new pesticide that it is advertising as being biodegradable and safe for using on food crops. The research work was done by a scientist who is employed by the same company which produces the pesticide, and the company is anxious to start marketing and selling the pesticide. Which of the following issues is the most troubling scientifically? A. The researcher has not gotten a patent to protect the design of the pesticide. B. The information has already been presented at trade conferences to salespeople and CEOs. C. The research has been reviewed by outside scientists who have financial investments in similar products. D. As a company employee, the researcher may have been biased when interpreting the experimental data. D is the correct answer since bias due to job protection or professional conflicts is likely. A is incorrect although obtaining a patent would give financial protection. B is incorrect since the inclusion of other scientists and their response is not apparent. C is incorrect since no information about the other scientists’ conclusion and the conflict of finances cloud the impact of this answer.
