To test the vaccine safety before its use on human, transgenic___________ are used to test. If successful,________are used to test the safety of vaccine-

Options

A. Mice, monkeys
B. Monkeys, mice
C. Cows, mice
D. Sheep, cows

Answer

To answer the question, we need to fill in the blanks regarding the testing of vaccine safety using transgenic organisms.

1. **Identify the first blank**: The first part of the question states that "transgenic _________ are used to test." In the context of vaccine safety testing, transgenic animals, particularly mice, are commonly used. These mice are genetically modified to express human genes, which makes them suitable models for studying human diseases and testing vaccines.

2. **Identify the second blank**: The second part of the question states, "If successful, ________ are used to test the safety of the vaccine." After testing on transgenic mice, if the results are promising, the next step typically involves testing the vaccine on larger transgenic animals, such as transgenic monkeys or other primates. These animals are closer to humans in terms of physiology and immune response.

**Final Answer**: To test the vaccine safety before its use on humans, transgenic **mice** are used to test. If successful, **monkeys** are used to test the safety of the vaccine.

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