Question

1. (10 points) You combine 0.2 g of yeast, 0.2 g of sucrose and 10 mL of water, place the mixture inside an uninflated balloon, then tie off the opening of the balloon. (a) Explain what you would observe over the next hour. (b) What would you observe if you added iodoacetate to the mixture? (c) What would you observe if the mixture contained lactose rather than sucrose?

Answer 1

a) yeast is a microscopic fungus that converts sucrose  into carbon dioxide. To make yeast active it should be under moist condition so water is added here. As time proceds balloon size increases due to Formation of more and more carbon dioxide . After an hour it reaches maximum size . On further it may explode .

b) using iodoacetate will decrease the formation of cardon dioxide by inhibiting fermentation reaction.iodoacetate acts as a barrier when reactants trying to react and stops the rate of reaction

C) Yeast do not have the lactase enzyme and cannot break down lactose. If you add lactaid, lactose will be broken down into glucose and galactose, which can be used by the yeast.