The heart has a right pump and a left pump. Blood from the body returns to the right side, which sends it to the lungs. Blood returns from the lungs to the left side, which sends it around the body. Arteries carry blood away from the heart; veins bring it back. The heart acts as two coordinated pumps in series. Its chambers generate pressure differences that move blood through pulmonary and systemic vessels, while valves limit backflow. Arteries are defined by outward flow and veins by return flow. Oxygen changes during exchange with lungs and tissues; the diagram’s blue/red convention does not show literal blood colour.
The human body · Discover & try
Where does blood travel next?
Reading level 5 of 5 · AdvancedChange
Word help
Artery
A vessel carrying blood away from the heart.
Vein
A vessel returning blood to the heart.
Valve
A structure that helps prevent backward flow.
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Flat route diagram, not an anatomical view. Colours label oxygen level; all blood is red. Playback follows one representative packet, not a real heartbeat.
What to look for
- Body → right atrium → right ventricle → lungs → left atrium → left ventricle → body.
- This is where blood picks up oxygen before returning to the left side.
- The left ventricle sends blood toward the body tissues.
Explain what you noticed
A vessel carries blood from the heart toward a kidney. Which name fits its direction?
Keep this idea: Direction defines an artery or a vein; the two heart–lung–body loops work together.
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Source material checked 2026-10-29. Explanations and activities by Nepedia. Source links do not imply endorsement.
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