Which element is present in proteins but not in carbohydrates?
Nitrogen
Oxygen
Hydrogen
Which elements are present in fats and oils?
Carbon and hydrogen only
Carbon and oxygen only
Carbon, hydrogen and oxygen
What is the chemical test for starch?
Iodine solution turns blue-black
Biuret reagent turns purple
Iodine turns yellow-brown
A brick red precipitate forms when a solution is heated with Benedict's reagent. What could this solution contain?
Glucose
Protein
Lipase
What is glycogen made from?
Glucagon
Glycerol
Why are proteins important in a balanced diet?
They provide vital minerals
They are a high energy source
They are needed for growth and repair
Which biological molecule contains the most energy?
Carbohydrate
Fat
Which reagent is used to test for the presence of fat?
Biuret
Limewater
Ethanol