year 4 - Digestive System

What an exciting afternoon - we made poo!

We recreated our digestive system by breaking up crackers and banana (chewing) into a zip lock bag (our stomach) and adding orange juice and water to represent saliva and stomach acid. We then churned the food to break it all down into small pieces before emptying the contents into a leg of a tight (small intestine.) Using peristalsis (muscle contraction) we squeezed the churned food through the small (and large) intestine so that the nutrients and water could be extracted into the blood stream. The waste was then forced into a paper cup (rectum) and then it was pushed through the hole (anus) to excrete the waste.