CONSIDERATIONS TO KNOW ABOUT ANIMALS

A chain of 3 tiny bones transmits seem waves through the middle ear. A muscular diaphragm separates the heart as well as lungs from the abdominal cavity. just the left aortic arch persists. (In birds the best aortic arch persists; in reptiles, amphibians, and fishes equally arches are retained.) experienced crimson blood cells (erythrocytes) in all