Food tests
What do you need to know: (test yourself and then expand the menu)
- The three main biological molecules are Carbohydrates (sugars), Lipids (fats) and Proteins.
- This procedure requires you to explain how to test and how to identify a positive test for each molecule.
- Starch (a carbohydrate) turns Iodine from Brown to Blue
- Glucose (a carbohydrate) turns Benedict's solution from Blue to Brick Red when heated
- Lipids when shaken with ethanol form an emulsion (white layer)
- Proteins turn Biruet solution from Blue to Purple or Lilac.
Which enzyme breaks down lipids and what are they broken down into?
Which enzyme breaks down lipids and what are they broken down into?
Lipases break down lipids into fatty acids and glycerol
Why do we need to digest our food?
Why do we need to digest our food?
Not such an easy answer, the correct wording is:
- To break large molecules into small ones so they can be absorbed into the blood in the intestines
Why do we need to eat lipids, proteins and carbohydrates?
Why do we need to eat lipids, proteins and carbohydrates?
Lipids are used in our cell membranes and can be used as a storage molecule (fat)
Proteins can be broken down into amino acids and rebuilt into other proteins. Proteins have many roles, so do not just say for muscle! They can be made into hormones, antibodies, enzymes and yes, in muscle fibres too
Carbohydrates are used in respiration to release energy.