Given a scientific passage and an answer, generate a question for the given answer.

Q: Passage: The jointed appendages of arthropods may be used as legs for walking. Being jointed makes them more flexible. Try walking or climbing stairs without bending your knees, and you'll see why joints are helpful. In most arthropods, the appendages on the head have been modified for other functions. Figure below shows some of the head appendages found in arthropods. Sensory organs such as eyes are also found on the head. Answer: walking

A: What may the jointed appendages of arthropods be used for?
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Q: Passage: Take a close look at this gorilla hand. The similarities to a human hand are remarkable. Comparing anatomy, and characterizing the similarities and differences, provides evidence of evolution. Answer: evolution

A: Comparing anatomy, and characterizing the similarities and differences, provides evidence of what process?
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Q: Passage: Prokaryotes include Bacteria and Archaea. An individual prokaryote consists of a single cell without a nucleus. Answer: prokaryotes

A:
What are bacteria and archaea examples of?
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