Ques:Q: What bodily defense can be acquired in an active or passive way, and can be natural or artificial? Choices: - skin - membrane - nerves - immunity A:

Ans:immunity
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Ques:Q: Why do sharks sense low levels of electricity? Choices: - to locate mates - to sleep - to reproduce - to locate prey A:

Ans:to locate prey
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Ques:Q: In which sphere of the atmosphere do the northern and southern lights occur? Choices: - lithosphere - stratosphere - ionosphere - thermosphere A:

Ans:thermosphere
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Ques:Q: What does blood pickup from the lungs to be carried throughout the rest of the body? Choices: - carbon - white blood cells - platelets - oxygen A:

Ans:
oxygen
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