Teacher’s Questions for Old Germs


Before reading:

  1. What is the longest-lived organism you can think of, and how old can it grow to be?
  2. Describe a few ways in which living things differ from dead things.

During reading:

  1. How old is the deep clay that the bacteria live in?
  2. Do scientists know the age of the single-celled bacteria that live in the muck? What are some of the age estimates?
  3. Where do the microbes get their food?
  4. Over 1,000 years, how much new sediment will settle onto the seafloor?
  5. How deep down in the muck did Roy’s team search for microbes?
  6. What pattern did Roy’s team discover between the bacteria and the oxygen content of the muck they live in?
  7. What two things are the deep-down bacteria not doing, which makes them different from any other known organism?
  8. How do these deep-down bacteria avoid growing in size and growing in number?
  9. How did the scientists determine that the bacteria were eating nutrients in the sediments?
  10. How common do scientists think long-lived, slow-growing bacteria are on Earth?
  11. Name two kinds of harsh environments on Earth where scientists have found single-celled bacteria living. Name two places beyond Earth where scientists believe similar organisms could be found.

After reading:

1. How will scientists study new kinds of life or alien life if they don’t know much — or anything — about it?


1. Should we redefine what it means for something to be alive based on the bacteria Roy’s team has been studying? Explain your answer.