Q: The earth is tilted on its what? Choices: - top - compass - radius - axis A:
axis
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Q: What organ do mammals have that is exceptionally large for their body size? Choices: - lungs - heart - liver - brain A:
brain
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Q: The outer layer of what anatomical structure is so tough that it keeps out most pathogens? Choices: - liver - steel - bark - skin A:
skin
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Q: During adulthood, what is needed for the production of sperm? Choices: - steroids - estrogen - androgen - testosterone A:
testosterone
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