Biology IGCSE Food Tests Quiz

What color indicates a positive test for starch when iodine solution is added?

• Brown

• Blue black

• Green

• Red

What is the method used to test for reducing sugars?

• Add Biuret reagent

• Add Benedict solution and heat

• Add ethanol and water

• Add iodine solution and observe color change

What color change indicates a positive result for reducing sugars?

• Blue to green/red

• Blue to purple

• Blue to colorless

• Brown to blue

Which reagent is used to test for proteins?

• Iodine solution

• Benedict solution

• Biuret reagent

• DCPIP blue dye

What is the expected result for a positive fat test?

• Colorless

• Blue color

• Brown color

• Milky white precipitate

What is the method for testing fats?

• Emulsion test with ethanol and water

• Add iodine solution

• Add Biuret reagent

• Add Benedict solution

What color change indicates a positive test for vitamin C?

• Green to red

• Blue to colorless

• Brown to blue

• Colorless to blue

What is the expected result for a negative test for starch?

• Remains purple

• Remains colorless

• Remains brown

• Remains blue

In the emulsion test for fats, what is added after ethanol?

• Benedict solution

• Biuret reagent

• Iodine solution

• Water

What is the temperature at which the reducing sugar test should be heated?

• 70 degrees Celsius

• 80 degrees Celsius

• 90 degrees Celsius

• 60 degrees Celsius