Question

suppose an alien life form is discovered on another planet that takes in CH4 from the atmosphere. which of the following could be used to determine what happens to the CH4 after the organism consumes it?

Answer 1

"PET scanners are often used to track molecules through the body. Basically, the subject ingests a radioactive isotope (basically an element with more neutrons than normal) and it is tracked with the scanner through the body. You could do the same thing by taking a radioactive CH4 isotope and following it with the scanner. "