30. A virologist develops a way to weaken a deadly virus and then injects this weakened virus into mice. The mice live. When subsequently exposed to the original deadly virus, none of the mice become sick. Which of the following has the virologist potentially developed?
Answer: C
The virologist has potentially developed a vaccine for the deadly virus.
By weakening the deadly virus and injecting it into mice, the virologist is likely stimulating an immune response without causing illness. This is the fundamental principle behind the development of vaccines, which prepare the immune system to fight against future infections with the original virus.
A) An anesthetic for the deadly virus
An anesthetic is a substance that induces insensitivity to pain or consciousness, and it does not have any role in preventing viral infections. Therefore, this option is incorrect as it does not relate to the immune response or the context of the virus being weakened and then tested.
B) Gene therapy for the deadly virus
Gene therapy involves altering the genes within an individual's cells to treat or prevent disease, which is not applicable in this scenario. The virologist’s approach focuses on using a weakened form of the virus to build immunity rather than modifying genetic material, making this option incorrect.
C) A vaccine for the deadly virus
This option is correct as vaccines are designed to expose the immune system to a harmless form of the pathogen, thereby training it to recognize and combat the actual virus in the future. The scenario describes exactly this process, where mice survive the weakened virus and are protected from the original strain.
D) An antibiotic for the deadly virus
Antibiotics are used to treat bacterial infections and have no effect on viruses. Since the context involves a virus, this option is not applicable and therefore incorrect.
Conclusion
The correct answer is C, as the process described aligns with the principles of vaccination, where a weakened strain of a virus is utilized to provide immunity against future infections. Options A, B, and D do not relate to the fundamental mechanism of immunity development and thus fail to address the question accurately.