DENDROLOGY

Detailed explanation-1: -Iodine that was added to the food reacts with the starch present in it. This forms a Starch-Iodine complex that is blue-black. Thus, the appearance of colour change to blue-black colour confirms the presence of starch in the food item. Blue-black colour indicates the presence of starch in the tested food item.

Detailed explanation-2: -Test for Carbohydrates: Molisch’s test – Given sample food + Molisch’s reagent → Purple or violet ring confirms the presence of carbohydrate. Fehling’s test – Given sample food + Fehling’s reagent → Red precipitate confirms the presence of carbohydrates.

Detailed explanation-3: -Sudan III is used to identify the presence of lipids in liquids. It will stain fat cells red.

Detailed explanation-4: -Energy storage molecules are those molecules which store energy in the form of covalent chemical bonds. Some molecules like glycogen (carbohydrate) and triglycerides (lipids) are synthesized by the cells and they are stored for the later release of energy. So, the correct answer is “both lipids and carbohydrates".