Chapter 2 – Food
Revision questions
- Name the 3main compounds contained in foods.
- what other substances does food also contain?.
- What elements are present in carbohydrates?
- What is special about the ratio of hydrogen to oxygen in carbohydrates.
- What is the function of carbohydrates?
- What are the carbohydrates sucrose and starch broken down to in the digestive system?
- The word equation for cellular respiration is oxygen + glucose gives carbon dioxide + water + energy. Where does the glucose come from?
- Complete the following table:
| Carbohydrate |
Example |
Function |
Test |
| Monosaccharide |
|
|
|
| Disaccharide |
|
|
no test |
| Polysaccharide |
|
|
|
| Polysaccharide |
|
|
no test |
- Explain how a food can be tested for the presence of glucose. What colour change indicates a positive result? What colour changes might be observed if only a slight amount of glucose is present?
- What is the test for starch? What colour change indicates a positive result?
- List some food sources of carbohydrates.
- What is the function of cellulose?
- What elements are present in fats and oils?
- what is another name for fats and oils?
- What is the function of fats and oils? How does their energy value compare with carbohydrates?
- Compare carbohydrates and fats and oils. (Remember comparing means consider what is similar and what is different.)
- List some food sources of fats and oils.
- What are fats and oils broken down to in the digestive system?
- What elements are present in proteins?
- What are smaller units that make up proteins?
- What is the function of proteins?
- What are proteins broken down to in the digestive system?
- What are essential amino acids?
- How can we test foods for the presence of proteins? What colour change is observed if protein is present?
- Compare proteins and carbohydrates.
Fill in the gaps
__________________ is any chemical substance that an organism needs to survive and function properly. Our _______________ includes food that we eat and drink. The product of digestion of carbohydrates (except for cellulose) is ________________. The carbohydrate that cannot be digested by man is _________________. _____________________ on average produces twice as much energy as carbohydrates. ___________________ are solid at room temperature and ___________________ are normally liquid at room temperature. another name for fats and oils is ______________. These are broken down to ________________ and ___________________ during digestion.. Animal fats provide some _________________ against the cold and are stored _________________ and _____________. The main function of proteins is __________________ and ________________. The basic building blocks of proteins are ________________________. These _____________________ are used by humans to build proteins. There are about _________________ different ones needed. Important amino acids that must come from our diet are called ________________ amino acids. The main sources of protein are ____________________. Lack of vitamins causes ____________________ diseases.
___________________ has no essential food value, but must be included in our diet. It is important to our body because it makes up a large proportion of all human tissue. It is also important because it acts as a medium for all the transport mediums within the body.
Updated by Mrs Ariotti 14/03/08
|
