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: Which proteins recognize and combine with harmful materials, including both toxic chemicals and invasive microorganisms? Answer: antibodies

Answer: Antibodies recognize and combine with harmful materials, including both toxic chemicals and invasive microorganisms.


Question: Question: What describes the amount of solute in a solution? Answer: tonicity

Answer: Tonicity describes the amount of solute in a solution.


Question: Question: What is the smallest class of elements? Answer: metalloids

Answer:
Metalloids is the smallest class of elements.