In animals, this could be hibernation, which slows down the animal's metabolism so that it can get along on less food and water. Mammals, like bears, hibernate, but so do frogs, toads, and other cold-blooded animals.
Plants also undergo a winter slowdown.
Try growing apple seeds fresh from the apple. Try others that you have rinsed in water and then stored in moist sand in the refrigerator for a few weeks. Cut some branches of willow or box elder, place them in water, and see if you can get them to leaf out. Dig up some mud from near a pondUs edge or from under the ice, get some pond water as well, and put it all in a large glass jar. It will look cold and lifeless.