1.lungs (because the lungs is each of the pair of organs situated within the rib cage, consisting of elastic sacs with branching passages into which air is drawn, so that oxygen can pass into the blood and carbon dioxide be removed.doesn't connected in the heart.
2.antigens (because a toxin or other foreign substance that induces an immune response in the body, esp. the production of antibodies.because the three is the composition of the blodd."
>Hope it helps
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