The Digestive System

Keywords

Digestive system, stomach, oesophagus, small intestine, large intestine, rectum, anus, liver, saliva glands, pancreas, gallbladder, food processing, enzymes, breakdown, amylase, protease, pepsin, lipase, metabolism.

Introduction

When we eat, our body processes the food through a system that breaks down food and removes nutrients for us to use elsewhere.

What Organs are Included?

So, from the top, your food enters your mouth, and goes through the following organs:

The digestive system also uses and includes the following:

Interesting fact: the stomach can hold up to a litre of food at any given time.

Food Processing

How is our food processed once we've eaten?

Once you've taken a bite of your food, what do you usually do? You chew it. But what happens to it after that?

Well, for this example we will call the bit of food you've eaten a food parcel. The food parcel moves down the oesophagus and into the stomach. When it sits in the stomach, it gets broken up into smaller pieces in order to pass through to the intestines. This process is done using acid, called bile. This bile is produced by the liver, and stored in the gallbladder until needed.

Once it is small enough to move into the small intestines, it does so. So, your food parcel up to here has moved down a food pipe, and sat in some acid to deteriorate into smaller chunks. Are we ready for what is next?

Enzyme Breakdown

Once in the small intestine, the food parcel is subjected to nutrient testing. I'm going to call it that, as it is like a massive checkpoint. Your food parcel will have targeted minerals and nutrients that the body needs (vitamins, sugars, fats, etc), and the enzymes that work with it will break these down into products using an active site (please see the enzyme picture in the resource). This is done to make glucose and fructose from the food parcel.

Sounds simple so far, right? That's because in this manner it is. That is the simplest way to explain how an enzyme works. There are several types of enzyme in our body. They are:

Enzymes and Metabolism

Enzymes can work fast, breaking down nutrients into glucose and fructose, or they can work slow and be lazy. This can affect our body in another way, other than just how much energy we have. Enzyme breakdown attributes to our metabolism. A metabolism is a series of chemical processes that allow us to grow, create heat, lose or take on weight, and other factors.

There are two types of metabolism people can have:

High metabolism: this is where you're able to burn calories faster than the average person. It has its advantages, but it's drawback is that you can use up too much energy, or you have trouble gaining any substantial weight.

Low metabolism: this is the opposite of a high metabolism. You will find it easy to gain weight, you might have too much energy, and your body won't burn the calories as fast as the average person.

Your body can go from having a low metabolism to having a high metabolism, simply by exercising more and increasing your lean muscle mass. This turns the fat in your body to muscle, and will probably make you feel better as a result.

The End of the Road

Your food parcel has gone through a lot. By this point, it has gone in the mouth, down the windpipe (oesophagus), through the stomach, through both intestines, and now it sits in the rectum. What does it do here? Well, it is stored until, you know. Until you need to go. By this point, it has no nutrients, and almost everything needed in it has been removed. It is time for removal. The rectum and anus are also included in the excretory system, and their function is to remove waste product from your body.

At the very end of your digestive system is something called a sphincter. This is a small valve that acts like an opening to allow waste product to pass through. When the rectum is full, and you need to poop (ergh, there, you made me say it!) the sphincter opens to allow it to pass.