Breathing and digestion
Does chewing start digestion before you swallow?
Does bread taste sweeter the longer you chew it?
Watch first
An English teaching video on this topic from Amoeba Sisters. Watch it, then scroll down for the lesson.
What you need
Tick each one as you find it — 0 of 3 ready.
Plan the fair test
- Change: How long you chew for
- Measure: How sweet it tastes, scored out of five
- Keep the same: Same bread, same size piece, rinsing between tries
Objectives this evidences
- Understand the tissues and organs of the human digestive system, including the role of enzymes and the importance of bacteria in the gut
Do it, one step at a time
Step 1 of 4
- Step 1. Chew a small piece of bread for five seconds and note the taste, then swallow.
- Step 2. Rinse with water. Chew a second piece for thirty seconds without swallowing, and note the taste.
- Step 3. Rinse again and repeat with a full minute of chewing.
- Step 4. Score the sweetness out of five each time and record it in a table.
What should happen
It gets sweeter, because an enzyme in saliva breaks starch into sugars.
Think about: Sweetness scores are opinions, not measurements. How does that weaken your conclusion?
Write up your result
A sentence or two is enough to save it.
The lessons behind this practical
Each one opens with the same short film, and the film has a written transcript underneath if reading is easier than watching.
Now the quiz for this topic
Questions come from the lessons behind this practical, so nothing is asked that has not been taught.
Quiz
Breathing and digestion quiz
4 questions from the lessons in this stage. No timer, and you can try again as many times as you like.