In this task, you are given a question and an answer, you would be asked to create the sentence based on the Question-Answer provided. It should be contained within the Question-Answer provided.

Q: Question: Acting like drawstrings to close off the alimentary canal, what regulates the passage of material between compartments? Answer: sphincter

A: Acting like drawstrings to close off the alimentary canal, the sphincter regulates the passage of material between compartments.
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Q: Question: When does exchange of dna segments happen between non-sister chromatids of homologous chromosomes? Answer: during crossing-over

A: Exchange of dna segments happens between non-sister chromatids of homologous chromosomes during crossing-over.
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Q: Question: What bodily function do the triceps help perform? Answer: extend the arm

A:
The triceps help the body extend the arm.
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