Inside the Heart: Four Chambers, Valves and Open Vessels

A cutaway drawing of the human heart shows the four inner chambers outlined with thick, clean lines. The thick muscle wall surrounds the chambers, and thin valve flaps are drawn between the upper and lower sections. Large tubes come off the heart. Three open-ended vessels stick out on the left side, one wide vessel runs down at the bottom, and a big curved vessel arches across the top with branches rising above it. On the right side, two more short tubes extend outward. There are no labels, so the page is ready for your own notes. Try coloring the left and right sides in different colors, such as blue and red, to show how blood moves through the chambers. It works well for a science lesson, and students can add their own labels once they have colored it in.