First blood enters into the top right chamber, the right atrium, stop there for a moment then drops down into the bottom right chamber, the right ventricle. When your heart beats the used blood in the bottom right chambers shoots out of the heart and through an artery into you lungs.
indicator - (chemistry) a substance that changes color to indicate the presence of some ion or substance; can be used to indicate the completion of a chemical reaction or (in medicine) to test for a particular reaction.
n. 1. (Chemistry) any substance used in or resulting from a reaction involving changes to atoms or molecules, especially one derived artificially for practical use. adj. 2. (Chemistry) of or used in chemistry: chemical balance. 3. (Chemistry) of, made from, or using chemicals: chemical fertilizer.(ËkÉm Éª kÉl). n. adj.. a substance produced by or used in chemistry. 2. chemicals, Slang. narcotic or mind-altering drugs or substances. 3. of, used in, produced by, or concerned with chemistry or chemicals: a chemical formula. 4. used in chemical warfare: chemical weapons.