The wood frog freezes solid in winter and thaws in spring.
Why it is true
Its liver produces large amounts of glucose that acts as a natural antifreeze. This protects the cells from damage while the heart and breathing stop for several months.
Source: Scientific American
Would you rather be asked first?
This is the reading side of the site, so the answer is in the sentence above — that is the whole point of it. Test yourself works the other way round: the question comes on its own, and the fact and the explanation only appear once you have answered.