yeast

In the yeast discovery lab we had to decided what the outcome would be then perform the experiment. The experiment was done during class time, so everyone’s results would be the same. There were four bottles with warm water in them and to those bottles were added yeast. Then to one of each bottle there was added sugar, corn syrup, corn starch. To the fourth bottle there was only yeast added and used as a control group. Balloons were then stretched onto the top of the bottles to catch any gas the yeast would produce to see if yeast is a heterotrophs or autotrophs. The bottle with the yeast and sugar produced much carbon dioxide because yeast eats the sugar to produce gas and make whatever the yeast is put in airier. When yeast eats sugar it produces a by-product which is alcohol. The bottle with corn syrup and yeast didn’t produce much gas, because the sugar has been broken down into a liquid state. So the yeast doesn’t have the sugar molecules to consume. The corn starch and yeast didn’t produce any gas because corn starch does not dissolve in water and there is no sugar for the yeast to eat. The bottle with just yeast produced some carbon dioxide but not very much. Water awakens yeast from its dormant state but with no sugar to metabolize the yeast stops producing gas. Yeast is a heterotroph, in order to produce energy it needs a food source and in the case of yeast that would be sugar. Yeast will also use sugar to produce alcohol, wine and beer production would not be possible without yeast. Only sugar and yeast have this reaction there is no other substance that is known that will have this same reaction with yeast.