Detailed Instructions: Given a scientific passage and an answer, generate a question for the given answer.
Q: Passage: With the naked eye, bacteria just look like a slimy smear on a petri dish. How can we study them in more detail? The invention of the microscope has allowed us to see bacteria, cells, and other things too small to be seen with the naked eye. Answer: slimy smear
A:
How does the bacteria look when seen with the naked eye?