Our 3rd grade students (MYP4) have been investigating the presence of proteins and starch in different types of food during their Biology class.
To do this, their teacher Ana has been teaching them how to use different reagents to test for their presence in foods such as bread or milk as part of their Unit of Inquiry “What’s in the food you eat?”
Using the balance and pipette, they mixed milk with a solution of copper sulfate and potassium hydroxide to see that the milk turns purple! This indicates the presence of proteins. In the case of bread, lugol was used to confirm the presence of starch, because when a drop of this reagent was added, its color changed from orange to black. During the practice, the necessary safety measures were adopted, such as the use of gloves, goggles and gowns.
With this type of activity they work on different attributes of IB: thinkers, knowledgeable and inquirers through the design of experiments, presentation of results and conclusions.