trace the movement of oxygenated blood in the body
The oxygenated blood starts from the lung and moves to left atrium. The blood gets collected there when it relaxes. After it contracts, the blood enters left ventricle. Form there it is circulated to whole of the body. If you study NCERT books, you can refer to class 11ths biology textbook and see chapter circulation. Everything is explained diagrammatically.
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