Informational (nonfiction), 1,871 words, Level V (Grade 4), Lexile 960L
Readers will learn that one drop of blood contains more than 5 million red blood cells, but they'll be amazed when they find out that if all the arteries, veins, and capillaries in the body were stretched end to end, they would reach across the United States 20,000 times! These and other facts about the circulatory system are included in the Book of Blood. Types of blood vessels, blood cells, and blood types are explained. Photographs, illustrations, and a diagram showing how blood is pumped through the heart help readers connect with the text.