Mad cow disease, or bovine spongiform encephalopathy, appears to be caused by a novel infectious agent: a protein that replicates by causing related proteins to modify their structure from a harmless shape to a dangerous one. These prions (short for “proteinaceous infectious particles”) also appear to be the cause of several other spongiform encephalopathy diseases, such as scrapie in sheep, and kuru and Creutzfeldt-Jakob disease in humans. Which of the following observations or experiments would not support the hypothesis that a prion causes spongiform encephalopathy? (a) The brains of many sheep with scrapie contain prion proteins, but the brains of most sheep without scrapie do not. (b) There is a high incidence of kuru in populations of people who consume brain tissue from prion-infected animals. (c) Coyotes that feed on cows with mad cow disease do not subsequently develop spongiform encephalopathy. (d) When introduced into sheep brain cells in culture, prions cause the normal proteins to change shape into dangerous prion proteins. (e) When prions are fed to sheep, most of them subsequently develop scrapie, whereas sheep not fed prions do not develop scrapie.
Mad cow disease, or bovine spongiform encephalopathy, appears to be caused by a novel infectious agent: a protein that replicates by causing related proteins to modify their structure from a harmless shape to a dangerous one. These prions (short for “proteinaceous infectious particles”) also appear to be the cause of several other spongiform encephalopathy diseases, such as scrapie in sheep, and kuru and Creutzfeldt-Jakob disease in humans. Which of the following observations or experiments would not support the hypothesis that a prion causes spongiform encephalopathy? (a) The brains of many sheep with scrapie contain prion proteins, but the brains of most sheep without scrapie do not. (b) There is a high incidence of kuru in populations of people who consume brain tissue from prion-infected animals. (c) Coyotes that feed on cows with mad cow disease do not subsequently develop spongiform encephalopathy. (d) When introduced into sheep brain cells in culture, prions cause the normal proteins to change shape into dangerous prion proteins. (e) When prions are fed to sheep, most of them subsequently develop scrapie, whereas sheep not fed prions do not develop scrapie.
Step by step
Solved in 2 steps
