Most women have had a pregnancy scare at least once, and at home test are sold everywhere aroundthe United States . I love my own son, but this class made me wonder what makes the test work ? Beforea woman knows she is pregnant her body makes chorionic gonadotropin/hGC that is found in the bloodand urine. Pregnancy tes15t can detect the protein called antibodies interlaced on the urine strip. Thereare three zones of function. Antibodies tie to the hGC molecule and becomes an anti-hGC antibody. Dyealso participates in the color reaction. The urine of the pregnant woman yields a positive test result. Todetermine this result the test strip is dipped in the sample/stream . The sample with hGC is drawn up thestrip and arrives at the reaction zone. The enzyme-linked antibodies recognize parts of the hGCmolecules and binds to the urine. At the test zone, other anti-hGC antibodies bind to the hGC portions ofthe moving complexes. The antibodies in this zone are permanently affixed to the strip so the complexesthat bind her stay. The free antibodies continue to flow along the strip. In the test zone the enzymelinked antibodies catalyze a reaction with the dye molecules, which act as substrates, and trigger a colorreaction. In a positive test two of the three bands are colored, but in a negative test only one is colored. If the woman is not pregnant when the urine flows to the reaction zone antibodies have nothing to bindto. Female humans and animals get pregnant every day in nature but the hGC and antibody reactionhappens in a controlled environment. The consequence(happy or not) of this reaction is the futuredevelopment of a child. If the reaction takes place a woman can tell because the dye links and shows inthe results box. I believe the reaction is an exergonic reaction, energy is released to the surroundings. Asthe urine slows along the strip it is releasing energy to allow antibodies to react and release dye orcontinue to flow. The reaction is not reversible. Work Cited: ",Animation. ", Animation. Sumanas, Inc. Web.