Question 14

Sommer's conclusion is based on examining the genes, while O'Brien's conclusion is based on acceptance of a skin graft.

Sommer's research provides a more comprehensive analysis of gene variation by directly examining the genetic material of a larger sample of wild cheetahs, allowing for a clearer understanding of their MHC gene diversity. In contrast, O'Brien's conclusion was drawn from the observation of skin graft acceptance, which does not provide as detailed an insight into the genetic variability present within the population.

A) Sommer's research was conducted more recently than O'Brien's

While it is true that Sommer's research was conducted more recently, the validity of a conclusion is not solely dependent on the timing of the research. The depth of analysis and methodology employed is more crucial in determining the robustness of the conclusions drawn.

B) Sommer's research used a different population of cheetahs than O'Brien's

This statement is not accurate in the context of validating Sommer's conclusion over O'Brien's. Although different populations might yield different results, the key factor is the methodology and the comprehensiveness of the genetic analysis, not merely the populations studied.

C) Sommer's conclusion is about disease response, while O'Brien's is about skin grafts.

This option highlights a difference in focus but does not directly address the validity of the conclusions. O'Brien's focus on skin graft acceptance relates to immunological compatibility rather than broader genetic diversity, which is critical for understanding overall disease resistance in cheetahs.

D) Sommer's conclusion is based on examining the genes, while O'Brien's conclusion is based on acceptance of a skin graft.

This option correctly identifies the methodological difference that contributes to the validity of Sommer's conclusion. By examining the genes directly, Sommer was able to assess genetic variation comprehensively, whereas O'Brien's conclusion relied on a more limited observation regarding immunological response to transplants.

Conclusion

Sommer's research provides a more detailed and scientifically rigorous exploration of gene variation among cheetahs, focusing on genetic analysis rather than immunological implications from skin grafts. This thorough approach allows for more reliable conclusions regarding the cheetah population's ability to respond to diseases, in contrast to O'Brien's findings, which lack the same depth of genetic insight.