Discover the circulatory system and play a game in this Flash Activity by guiding a red blood cell on its journey through the body. Learn about a doctor who helped infants with a certain type of heart defect or read the text-only version.

Find out about some of the tools that doctors use to examine their patients. See what a doctor might see, hear what a doctor might hear—and test your own observation skills with this Flash Activity. Learn about a doctor who transformed the way babies are examined at birth or read the text-only version.

Find out about this hereditary disease that affects the blood. Determine the risks with this Flash Activity for passing sickle cell anemia to the next generation. Learn about a doctor who made the study of this disease one of her life focuses or read the text-only version.

Zoom in on the action of this Flash Activity to learn how cells reproduce. Find out about a specific kind of mistake in cell reproduction called translocation, and test your ability to spot chromosomes with this type of error. Learn about a doctor who did groundbreaking work on translocation or read the text-only version.