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: A concave lens is thicker at the edges than it is in the middle.

Answer: What type of lens is thicker at the edges than it is in the middle?


Question: The amniotic egg first evolved in reptiles.

Answer: The amniotic egg first evolved in what species?


Question: The haploid gametophyte produces gametes through mitosis.

Answer:
By what process does the haploid gametophyte produce the gametes?