c<span>: The interdependence of body systems is essential because all systems work together to maintain homeostasis.</span>
Cells are the basic building blocks of life, which can join together to form tissues, while different groups of tissues join together to form organs. These organs are then connected together to form organ systems, such as the digestive system, which includes the stomach, esophagus, intestines and other organs.
Six thousand reindeer once lived on a remote island in the Bering Sea
that was briefly their paradise. In what has become a classic story of
wildlife boom and bust, no reindeer live on St. Matthew Island now.
Three scientists just looked back at the St. Matthew's reindeer herd and
found that an extreme winter probably pushed the stressed animals to
their deaths.