Today we looked at the human digestive system. We watched a short animation that helped us see how food travels through you body and what it does. We then had a sheet where we had to label the organs/parts of the digestive system.

 

Then we undertook an experiment to help us understand it.

In our pairs we started off with a plastic cup and fork. Miss Nicholson gave us food to mash. The fork demonstrated how teeth grinds up the food in the mouth. We were given banana, coco pops, cracker, crisps and sweetcorn. We mashed this all up then added water to represent the saliva. Saliva is a special chemical called enzymes which do the real work of breaking up the food and lubricates it so that it can be swallowed.

Once we made this watery past we swallowed the food down our esophagus (food tube) by emptying the cup into a sealed bag which was our stomach. Miss Nicholson came around with vinegar which was the stomach acid and we mashed our food some more to show the muscular contractions churning the food and mixing it with the digestive juices. Did you know that food can remain in the stomach for 3-4 hours.

After this process we emptied the contents of our stomach into a pair of tights, this represented our intestines. Digestion takes place in the small intestines. We showed this by squeezing the tights which took all the juices out. This was the nutrients we need for growth and energy leaving the intestines and flowing into the body. Food can be in the small intestines for 3 hours.

The food that we cannot digest along with bacteria turns into waste and passses into the large intestines, this was what was left at the bottom of the tights. The large intestines reabsorbs water in the blood and forms solid faeces. This can stay here for 18 hours upto 2 days! The waste is stored in the rectum until it is passed out of the body.

Did you know in your lifetime, your digestive system may have to process 50 tonnes of food! Now that’s a lot of food!!