Question 1. Sucrose digestion Sucrose is a common sugar. It is a disaccharide, a molecule composed of two monosaccharides: glucose and fructose. Sucrose is digested in the small intestine in the presence of the enzyme sucrase.

A student conducted the following experiment in order to know if sucrose is digested by a unicellular fungus called (yeast). Sucrose and water were put in 3 test tubes (A, B and C). Sucrase is added into tube (B) and yeast is added into tube (C). The tubes are left in water bath for 40 minutes at 37oC.
1A) State the problem that is at the origin of this experiment.

1B）Complete all the boxes with (+) to indicate the presence or (-) to indicate the absence of an item in the following table to illustrate the conditions of the experiment, some inputs are filled for you.