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.
1 When we want to decide whether a solution (in water) is acidic or basic, we can measure its pH. 2  One of the ways pH can be measured, is with an acid-base indicator, such as universal indicator. 3  An acid-base indicator is a substance that changes its colour depending on the pH of the solution that it is added to.e know that some substances change colour when they react with an acid or a base. These substances are called acid-base indicators, which can show us if a substance is an acid or a base. Different indicators change colour at different pH values.