What must happen before meiosis can begin?
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a. dna must duplicate four times.
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b. the chromosomes must replicate.
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c. four haploid cells are produced.
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d. the cell splits into four parts.

Hello! Your answer is B, the chromosomes must replicate.

Meiosis is a process which takes one diploid cell (46 chromosomes) and makes 4 haploid cells (23 chromosomes). In order to do this, the DNA must divide. This is because it takes 46 chromosomes, to make 4*23 chromosomes, or 92.

We see here that the amount of chromosomes must double before meiosis. This therefore means A is incorrect, as the DNA only needs to duplicate 2 times. This also proves B correct, as the replication of chromosomes is what we're looking for.

C and D are incorrect, as they are actual processes in meiosis, meaning they do not happen before.

Hope this helps!

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