Pupil sheet · Food tests
Food tests — return questions
Name ______________________ Date ____________
Use one to two weeks after the lessons. Keep the notes and the lesson closed.
1. state
Starch, glycogen and cellulose are all made from which smaller molecule?
Circle one answer.
- Amino acids
- Glucose
- Fatty acids
- A different sugar for each one
2. complete
Complete the sentences about food molecules.
Proteins are made from …
Fats and oils are made from …
… and …
As well as carbon, hydrogen and oxygen, proteins contain …
3. identify
Which food test needs the tubes to be heated in a water bath?
Circle one answer.
- Iodine test for starch
- Benedict's test for reducing sugars
- Biuret test for proteins
- DCPIP test for vitamin C
4. complete
Complete the sentences about food tests.
Iodine solution turns … with starch.
Biuret solution turns … with protein.
DCPIP loses its … colour with vitamin C,
and, with the same DCPIP and drop size, the fewer drops needed, the … vitamin C the sample contains.
5. describe / explain
A food is shaken with ethanol, and the clear ethanol is then poured into a tube of water. Describe what you would see if the food contains fat, and explain what causes it.
6. identify
In DNA, which base pairs with C?
Circle one answer.
- A
- T
- C
- G
7. describe
Describe the structure of a DNA molecule in three sentences: its shape, what each strand contains, and what holds the strands together.