Given scientific fact as input, generate the question from this fact such that it can be answered from the input.
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Question: Diffusion process helps absorptive protists absorb food molecules across their cell membranes.

Answer: Which process helps absorptive protists absorb food molecules across their cell membranes?


Question: All cells have the small size in common.

Answer: What do all cells have in common?


Question: When amino acids bind together, they form a long chain called a(n) polypeptide, which is an essential component of protein.

Answer:
When amino acids bind together, they form a long chain called what, which is an essential component of protein?