Human heart diagram

What this diagram shows

The heart is a muscle about the size of a fist that pumps blood around the body. This diagram is drawn as if you are facing the person, so the heart's right side is on your left. That trips up many students, so say it out loud first. The picture has eight parts to tap: the right and left atria, the right and left ventricles, the aorta, the pulmonary artery, the vena cava and the valves. Explore gives each part's name and a fact, Labels names everything, and Quiz me asks the student to find each part.

Below the picture, Beat makes the heart pulse and shows the blood flow: blue arrows for oxygen-poor blood heading to the lungs, red arrows for oxygen-rich blood heading to the body. Follow a drop of blood asks the student to choose every next stop, from the vena cava through the heart, out to the lungs, back again and out to the body.

Why tracing the path helps

The heart is really two pumps side by side. The right side sends blood on a short loop to the lungs; the left side sends it on a long loop to the rest of the body. Reading this in a textbook is easy to forget. Choosing each step yourself, and getting feedback when a choice is wrong, builds a mental map of the double loop that lasts much longer.

Common misconceptions

• Blood is not blue. Oxygen-poor blood is a darker red; diagrams use blue only to tell the two kinds apart.
• Arteries do not always carry oxygen-rich blood. Arteries carry blood away from the heart, so the pulmonary artery carries oxygen-poor blood to the lungs.
• Blood cannot pass straight from the right side to the left side. A wall of muscle called the septum keeps them apart, so blood must go through the lungs first.
• The heart is not on the far left of the chest. It sits near the middle, tilted a little to the left.

A 10-minute heart activity

• Ask the student to make a fist: that's roughly the size of their heart.
• In Explore, tap the four chambers and sort them into the right pump and the left pump.
• Press Beat and trace each colored arrow with a finger, saying where the blood is going.
• Run Follow a drop of blood without help, then talk about any wrong turns.
• Finish by finding a pulse at the wrist, counting the beats in 15 seconds and multiplying by 4.

Where this fits in school

• US, grade 4: NGSS 4-LS1-1 asks students to argue that animals have internal structures that support survival, and the heart is a classic example.
• US, grades 6 to 8: NGSS MS-LS1-3 asks for evidence that the body is a system of interacting subsystems, such as the circulatory and respiratory systems working together.
• England, Year 6: pupils name the main parts of the circulatory system and describe the functions of the heart, blood vessels and blood.
• England, GCSE (Years 10 and 11): students study the structure of the heart, its valves and the double circulation in more detail.

Learning more

Science is part of Eurekami's skill map, with lessons that draw science diagrams live and narrate them in English or Spanish. When a question is tricky, the AI tutor asks guiding questions so the student does the reasoning. For older students, Exam Prep includes GCSE Combined Science practice papers.