2.1) Copy and complete these sentences, using words from the list.
You may use each word once, more than once or not at all.
atoms       large             molecules          pieces         small
Teeth break down large lumps of food into smaller .................. Then, enzymes break down the large .................. of the nutrients in the food into small ........... .
This allows the nutrients to pass out of the alimentary canal through the wall of the ................... intestine.

2.2) The table shows the carbohydrate content of ten foods.

a: Which food contains the most carbohydrate?
b: Bolormaa ate 50 g of biscuits. How much carbohydrate did she eat?
c: Rice does not contain sugar. What kind of carbohydrate does rice contain?
d: What do the four foods that do not contain carbohydrate have in common?

2.3) The diagram shows part of the human alimentary canal.

a: Name parts A and D.
b: Give the letters of two labelled parts where protein digestion takes place.
c: Give the letter of one labelled part where digested nutrients are absorbed.

2.4) Rhianna tested two different foods using iodine solution and Benedict's solution.
These were her results.
spaghetti - went blue-black with iodine solution, went blue with Benedict's solution
honey - went orange-brown with iodine solution, turned brick red with Benedict's solution
a: Describe how Rhianna tested the foods with Benedict's solution.
b: Construct a results table and fill it in to show Rhianna's results clearly.
c: What conclusions can Rhianna make from her results?

2.5) Nakula investigated the effect of heat on amylase. Amylase is an enzyme that makes starch molecules break down into sugar molecules.
• Nakula put some amylase solution into two boiling tubes, P and Q
• He boiled the solution in tube P. He did not heat tube Q
• He waited until the solution in tube P had cooled down to room temperature.
• He added equal volumes of starch solution to tube P and tube Q
• After 10 minutes, he tested both tubes for sugar.
• Nakula found that there was sugar in tube Q but not in tube P.
a: What was the variable that Nakula changed in his experiment?
b: State two variables that Nakula kept constant in his experiment.
c: Nakula wrote this conclusion to his experiment:
'My results show that boiling destroys amylase'.
Explain how Nakula's results support his conclusion.