Methyl blue can act as an artificial hydrogen acceptor; when this dye is reduced by accepting hydrogen atoms it goes colorless. As such, it can be used to gauge the rate of respiration by measuring the time taken for it to turn colorless. Methyl blue, acting as a hydrogen acceptor, is decolonize during the respiration of yeast. By measuring the time taken for a fixed amount of the dye to be decolonize, the relative rate of respiration (a catabolic process) can be deduced. Results:The yeast mixture in test tube A turned blue at first but slowly changed back to its original color and stayed that way. The yeast mixture in test tube B turned blue and remained unchanged.
The yeast mixture in test tube A are alive, whereas the yeast mixture in test tube B are dead. Reactions: Methyl blue when reduced turns changes to a colorless methyl blue when it gains electrons, and can be oxides back to blue when it loses electrons (oxidation). Therefore, it can be deducted that reactions in the yeast ells during respiration reduces blue methyl.Extra: Methyl blue can be used as an indicator to determine if a cell, in this case yeast, is alive or not. The blue indicator turns colorless in the presence of active enzymes, thus indicating living cells.
However, if it stays blue it doesn’t mean that the cell is dead – the enzymes could be inactive/denatured. Methyl blue can inhibit the respiration of the yeast as it picks up hydrogen ions made during the process. The yeast cell cannot then use those ions to release energy.