An example of an analogy drawing upon a scientific concept:
"I am not here assuming that 'brain' and 'mind' are equivalent, but that the rather vague, but useful, concept of mind that links to our conscious experiences depends upon the well-defined organ, the brain… A useful analogy might be between molecules and substances. The macroscopic substance water is quite different in nature to a water molecule, but there is a direct and strong relationship between these levels."

Read examples of scientific analogies
Many examples of science analogies are listed in 'Creative comparisons: Making science familiar through language. An illustrative catalogue of figurative comparisons and analogies for science concepts'. Free Download.