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 is the name of the location in which a stream or river starts? Answer: source

Answer: Source is the name of the location in which a stream or river starts.


Question: Question: Which unit is used to express the amount of energy in food? Answer: Calorie

Answer: A calorie is used to express the amount of energy in food.


Question: Question: After fertilization, how many cells does a zygote form into? Answer: two

Answer:
After fertilization, a zygote forms into two cells.