Stomach

After Tanno and Iguda were swallowed, they travelled down a tube called the oesophagus that joins the back of the throat with the stomach, where digestion of food continues.

The stomach walls contain muscle which, when it contracts, churns the food up like a biological food blender.

The stomach also produces enzymes. These are important for breaking down the food chemicals so they can be absorbed by the body.

It takes about 2 to 4 hours for the partially digested food to move from the stomach to your small intestine, although liquids tend to leave more quickly.

Image credit: Anatomical models by Somso, image courtesy of Adam,Rouilly Ltd.

The stomach produces strong acid. This kills many harmful microorganisms that might have been swallowed along with the food. The walls of the stomach are lined with a special substance called mucus that protects them from being damaged from the acid. The mucus has to be replaced every 2 weeks.

The model in the picture shows a close up of the stomach lining, where a fundic gland produces hydrochloric acid.

Image credit: Anatomical models by Somso, image courtesy of Adam,Rouilly Ltd.

While swallowing food, we also swallow air. To get rid of this gas, we often burp!

When you blush, the lining of the stomach turns red too!

Tanno protected the Microwidget by using his indigestion tablets (which contain an alkali) to neutralise the dangerous stomach acid. These experiments show you a similar reaction:

Activity 1

Neutralisation reactions 1

yellow fruit on white table

Photo by cottonbro on Pexels.com

1. Roll a couple of fresh lemons on a kitchen counter like dough. This releases the juice inside the lemon.

2. Cut the lemon in half (get an adult to do this part!) and carefully squeeze out the juice into a small cup.

3. Into an empty glass place 1 tablespoon of baking soda.

4. Add 1 teaspoon of washing-up liquid to the baking soda.

5. Stir these up a bit. Pour the lemon juice into the cup and stir. Now watch the bubbles erupt!

Activity 2

Neutralisation reactions 2

flour in a jar

Photo by Kaboompics .com on Pexels.com

1. Fill a small, clean plastic bottle about one third with vinegar (your acid).

2. Use a spoon to fill a balloon with baking soda (your alkali). You might need someone to and hold the balloon open.

3. Put the opening of the balloon over the opening of the bottle so the top is sealed.

4. Now tip the baking soda from the balloon into the bottle.

5. Watch the neutralisation reaction take place. Where does the gas in the bubbles go?


You can go to the previous PostcardsFromTheBody secret page by clicking the places below.

Mouth
Photo of PostcardFromThe Mouth