Triclosan is an antimicrobial chemical used in many personal care items such as hand soap. Because of its chemical properties, small amounts of the substance can be absorbed through the skin. Recent concerns about exposure to triclosan have resulted in research about its safety. The concentration of triclosan in a person's body can be determined by a urinalysis.
The graph shows results from a study that sought to determine average exposure to triclosan in the U.S. population. Which statement is supported by the results in the graph?
- A. Triclosan concentration does not vary significantly among different age groups.
- B. Increased levels of triclosan in urine are related to increased age.
- C. Triclosan concentration in urine is highest in the 30- to 39-year-old age group.
- D. People aged 20-29 likely use more products containing triclosan.
Correct Answer & Rationale
Correct Answer: C
The data indicates that the highest triclosan concentration in urine occurs in the 30- to 39-year-old age group, supporting option C. This finding highlights a specific peak in exposure among this demographic. Option A is incorrect as the graph likely shows variation in triclosan levels across age groups. Option B misinterprets the data; the graph does not suggest that triclosan levels increase with age. Option D assumes usage patterns without evidence from the graph, which focuses on urinary concentration rather than product usage.
The data indicates that the highest triclosan concentration in urine occurs in the 30- to 39-year-old age group, supporting option C. This finding highlights a specific peak in exposure among this demographic. Option A is incorrect as the graph likely shows variation in triclosan levels across age groups. Option B misinterprets the data; the graph does not suggest that triclosan levels increase with age. Option D assumes usage patterns without evidence from the graph, which focuses on urinary concentration rather than product usage.
Other Related Questions
Which statement correctly summarizes this information?
- A. Hemochromatosis is a dominant genetic disease caused by a single mutation.
- B. Hemochromatosis is a recessive genetic disease, but is caused by a lack of iron.
- C. Hemochromatosis is a recessive genetic disease, but the expression differs in individuals.
- D. Hemochromatosis is a dominant genetic disease that can be caused by several different alleles.
Correct Answer & Rationale
Correct Answer: C
Hemochromatosis is indeed a recessive genetic disorder, meaning that two copies of the mutated gene are typically required for the disease to manifest. Option A incorrectly categorizes it as a dominant disease, which does not align with its genetic inheritance pattern. Option B misstates the condition, as hemochromatosis is characterized by iron overload, not a deficiency. Option D also misrepresents the disease; while there are different alleles involved, hemochromatosis is primarily recessive, not dominant, making option C the most accurate summary of the information.
Hemochromatosis is indeed a recessive genetic disorder, meaning that two copies of the mutated gene are typically required for the disease to manifest. Option A incorrectly categorizes it as a dominant disease, which does not align with its genetic inheritance pattern. Option B misstates the condition, as hemochromatosis is characterized by iron overload, not a deficiency. Option D also misrepresents the disease; while there are different alleles involved, hemochromatosis is primarily recessive, not dominant, making option C the most accurate summary of the information.
Why is the conclusion about gene variation among cheetahs from Sommer's research more valid than the conclusion from O'Brien's research?
- A. Sommer's research was conducted more recently than O'Brien's
- B. Sommer's research used a different population of cheetahs than O'Brien's
- C. Sommer's conclusion is about disease response, while O'Brien's is about skin grafts.
- D. Sommer's conclusion is based on examining the genes, while O'Brien's conclusion is based on acceptance of a skin graft.
Correct Answer & Rationale
Correct Answer: D
Sommer's conclusion is more valid as it directly examines gene variation, providing a clearer understanding of genetic factors influencing traits. This direct analysis allows for more reliable insights into gene functionality. In contrast, O'Brien's research focuses on skin graft acceptance, which, while informative, does not provide the same depth of genetic examination. Option A is incorrect as recency does not inherently validate research findings. Option B is misleading; differing populations may affect findings but do not necessarily validate one conclusion over another. Option C misrepresents the focus of the studies; both are relevant but differ in application rather than validity.
Sommer's conclusion is more valid as it directly examines gene variation, providing a clearer understanding of genetic factors influencing traits. This direct analysis allows for more reliable insights into gene functionality. In contrast, O'Brien's research focuses on skin graft acceptance, which, while informative, does not provide the same depth of genetic examination. Option A is incorrect as recency does not inherently validate research findings. Option B is misleading; differing populations may affect findings but do not necessarily validate one conclusion over another. Option C misrepresents the focus of the studies; both are relevant but differ in application rather than validity.
A diagram of a PV cell being exposed to sunlight is shown below. Click on the labels you want to select and drag them into the boxes to show the components of the PV cell.
- A. Phosphorus-injected layer
- B. Boron-injected layer
- C. Electric field
- D. Energy
Correct Answer & Rationale
Correct Answer: A,B,C
The components of a photovoltaic (PV) cell include the phosphorus-injected layer, which serves as the n-type semiconductor, and the boron-injected layer, acting as the p-type semiconductor. Together, these layers create a junction that facilitates the movement of electrons when exposed to sunlight. The electric field between these layers is crucial for separating charge carriers, enabling electricity generation. Option D, "Energy," is not a structural component of the PV cell but rather a result of its operation. It does not represent a physical part of the cell, making it an incorrect choice.
The components of a photovoltaic (PV) cell include the phosphorus-injected layer, which serves as the n-type semiconductor, and the boron-injected layer, acting as the p-type semiconductor. Together, these layers create a junction that facilitates the movement of electrons when exposed to sunlight. The electric field between these layers is crucial for separating charge carriers, enabling electricity generation. Option D, "Energy," is not a structural component of the PV cell but rather a result of its operation. It does not represent a physical part of the cell, making it an incorrect choice.
Limestone and marble are often used in buildings. Both types of rock contain calcium carbonate, which is sensitive to chemical weathering by acids. A scientist conducted an experiment to test the effect of acid strength on calcium carbonate... Which change would reduce the possibility of error in the experiment?
- A. performing the experiment with a different acid in the solution
- B. performing multiple trials for each solution pH
- C. using more of the acidic solution
- D. using a solution with a pH below 3.00
Correct Answer & Rationale
Correct Answer: B
Performing multiple trials for each solution pH enhances the reliability of the experiment by allowing for the identification of consistent patterns and minimizing the impact of random errors. This approach provides a more accurate average result, leading to valid conclusions about the effect of acid strength on calcium carbonate. Option A introduces a variable that may not be relevant to the original question, potentially complicating the results. Option C does not address the variability inherent in a single trial, which could skew results. Option D restricts the experiment to a specific range of acidity, limiting the exploration of acid strength effects across a broader spectrum.
Performing multiple trials for each solution pH enhances the reliability of the experiment by allowing for the identification of consistent patterns and minimizing the impact of random errors. This approach provides a more accurate average result, leading to valid conclusions about the effect of acid strength on calcium carbonate. Option A introduces a variable that may not be relevant to the original question, potentially complicating the results. Option C does not address the variability inherent in a single trial, which could skew results. Option D restricts the experiment to a specific range of acidity, limiting the exploration of acid strength effects across a broader spectrum.