Question

what allows O2 to push in to our blood​

Answer 1

Answer:Inside the air sacs, oxygen moves across paper-thin walls to tiny blood vessels called capillaries and into your blood. A protein called haemoglobin in the red blood cells then carries the oxygen around your body.

Explanation:

Answer 2

Hey mate this is your answer

Oxygen is mixed in our blood by the process of diffusion. Then this blood is sent to our body parts by the muscular walls if our arteries by contractions and expansions.

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