During our Science lessons this week the children had to demonstrate how a banana sandwich passes through the digestive system. They used a variety of materials to illustrate what happens as it goes from our mouths to our stomachs to the intestine. They then created a flow chart to record the sequence of digestion and recorded what they learnt.

Photographs and writing by 4F

 

1

First we made our sandwich using two slices of bread and a banana which was cut in half and placed between the bread slices.

2

We used a knife - which represents the teeth - to cut the sandwich up.  We used a fork - which represented the back teeth - to grind and mash the food.

3

Next we added fairy liquid with a little red food colouring - this represented saliva - and  we continued to mush the sandwich.

4

When the consistency was correct we used a pop sock - which represented the oesophagus  - and we squeezed the mixture into it.  Eventually it reached the bottom of the sock and we cut a hole in the bottom of the sock and squeezed the mixture into a Ziploc bag - this represented the stomach.

5

The mixture then had some vinegar added to it with green food colouring - this represented bile -  and we continued to mush the mixture, which has now turned into chyme.  The Ziploc bag also doubled as the small intestine. 

6

Next we used our fingers - which represented the villi - and spread the mixture around the small intestine. This is where the nutrients are absorbed into the body. 

7

Eventually the mixture passes into the large intestine - the bottom of the bag - and into the rectum.  We cut a hole in the bottom of the bag and squeezed out the faeces (poo).

 

“After doing this experiment I now know that in the intestines and in the stomach the food turns into chyme.”  4F Pupil

“After doing this experiment I now know that the gallbladder stores bile which helps us to digest fat.” 4F Pupil