Problem:

Q: Which is larger: the human sperm or the human egg?   A:
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A: human egg


Problem:

Q: The major component of what cellular structures is the phospholipid bilayer?   A:
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A: cell membranes


Problem:

Q: Because plants lack what kind of system, their first line of defense is usually the death of cells surrounding infected tissue to prevent spread of infection?   A:
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A: immune system


Problem:

Q: What is the only continent without amphibians?   A:
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A:
antarctica