You are going to investigate the nutrient content of three types of drink: - drink A. - drink B - drink C. Read all the instructions but DO NOT DO THEM until you have drawn a table for your results in the space provided in 1(a)(i). You should use the safety equipment provided while you are doing the practical work. Step 1 Raise your hand when you are ready for hot water to be added to your hot water-bath for Test 1. Step 2 Test the drinks A, B and C using Tests 1, 2 and $$\(\mathbf{3}\)$$ Step 3 Record your observations in your table in 1(a)(i). Test 1 Testing for reducing sugars: - $$\(\quad\)$$ Label three test-tubes A, B and C. - Put $$\(1 \mathrm{~cm}^{3}\)$$ of drink $$\(\mathbf{A}\)$$ into test-tube $$\(\mathbf{A}\)$$. - Put $$\(1 \mathrm{~cm}^{3}\)$$ of drink $$\(\mathbf{B}\)$$ into test-tube $$\(\mathbf{B}\)$$. - Put $$\(1 \mathrm{~cm}^{3}\)$$ of drink $$\(\mathbf{C}\)$$ into test-tube $$\(\mathbf{C}\)$$. - $$\(\quad\)$$ Add $$\(1 \mathrm{~cm}^{3}\)$$ of Benedict's reagent to each test-tube. - $$\(\quad\)$$ Put all three test-tubes into the hot water-bath prepared in Step 1. - $$\(\quad\)$$ Start the stop-clock and leave the test-tubes in the water-bath for five minutes. - After five minutes, remove the test-tubes from the water-bath and place them in the test-tube rack. Test 2 Testing for starch: - $$\(\quad\)$$ Place two drops of each drink onto a white tile. - Add two drops of iodine solution to each drink sample. Test 3 Testing for protein: - $$\(\quad\)$$ Label three test-tubes A, B, and C. - $$\(\quad\)$$ Put $$\(1 \mathrm{~cm}^{3}\)$$ of drink $$\(\mathbf{A}\)$$ into test-tube $$\(\mathbf{A}\)$$. - Put $$\(1 \mathrm{~cm}^{3}\)$$ of drink $$\(\mathbf{B}\)$$ into test-tube $$\(\mathbf{B}\)$$. - $$\(\quad\)$$ Put $$\(1 \mathrm{~cm}^{3}\)$$ of drink $$\(\mathbf{C}\)$$ into test-tube $$\(\mathbf{C}\)$$. - Add $$\(1 \mathrm{~cm}^{3}\)$$ of biuret reagent to each drink sample. Three types of food contain different concentrations of the enzyme catalase. Catalase catalyses the breakdown of hydrogen peroxide to release water and oxygen gas: hydrogen peroxide $$\(\rightarrow\)$$ water + oxygen The production of oxygen gas can be used to measure the activity of the enzyme. Plan an investigation to compare the concentrations of catalase in the three types of food.

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