Science The Human Body Conceptual 9–11 yrs

Circulation & Breathing Together

循环与呼吸的协作

Description

Understand how the circulatory and respiratory systems work together: the lungs oxygenate the blood, the heart pumps it around the body, cells use the oxygen and produce carbon dioxide waste, and the blood carries the waste back to the lungs to be breathed out

Mastery Evidence

✓ Describe the cycle: lungs add oxygen to blood → heart pumps oxygenated blood to body → cells use oxygen → blood returns CO₂ to lungs
✓ Explain why heart rate and breathing rate increase during exercise (muscles need more oxygen)
✓ Measure their own resting and post-exercise heart rate and explain the difference

Assessment Prompt

Can your child explain why their heart beats faster when they run — and how their heart and lungs are working together to deliver more oxygen to their muscles?