Welcome to Slow English FM’s Daily Random Facts. We share clear, simple stories about the world to help you understand it and improve your English. This episode is about how wood frogs can survive winter.

In winter, ice can form around a wood frog’s cells. Yet the frog can survive. The ice is around the cells, not inside them. Large amounts of sugar help protect the cells from freezing. This is a special way for the frog to get through cold weather. The sugar does not stop ice from forming around the cells. Instead, it helps protect the cells themselves. The National Park Service describes this winter survival ability in its information about wood frogs. It is a striking example of how an animal can survive even when ice forms in its body. The key detail is the difference between ice around the cells and the cells themselves freezing. Wood frogs can survive winter because sugar helps protect their cells.