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.
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Question: Question: What substance is created when a copper turns from reddish brown to greenish brown? Answer: copper oxide

Answer: Copper oxide substance is created when a copper turns from reddish brown to greenish brown.


Question: Question: Growth factors and certain plant and animal hormones serve as molecular messengers that initiate pathways of what? Answer: cell division

Answer: Growth factors and certain plant and animal hormones serve as molecular messengers that initiate pathways of cell division.


Question: Question: What usually causes fractures on a bone? Answer: excessive bending stress

Answer:
Excessive bending stress usually causes fractures on a bone.