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Why does blood return to the heart between two journeys?

Blood travels from the body to the right side of the heart, onward to the lungs, and back to the left side before being pumped around the body again. The two connected circuits do different jobs. The pulmonary artery is a useful reminder that an artery is defined by the direction of flow, not simply by oxygen content.

5–7 min

Questions you could explore

  • What changes as blood passes through the lungs?
  • How do the pulmonary and systemic circuits connect without mixing their roles?

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Why does blood return to the heart between two journeys? | Speech Topic | speaking.app