Source: Video and Images Created by Amanda Soderlind
Welcome to this lesson titled digestive system overview. Today we will be taking a look at some of the basic structures and functions associated with the digestive system.
So basically the digestive system, if we were to break it down as easily as possible, we could say it's like one large tube that has two openings, one where food enters and the other opening where the waste exits. And then in between those parts is where nutrients are absorbed.
So there are actually five main functions of the digestive system that we're going to take a look at here. One function is that it mechanically processes food. The next is that it digests food. It secretes enzymes, absorbs nutrients, and eliminates waste. So these are the five main functions of the digestive system.
Now if you're interested in finding out more specifically about each of these, like enzyme secretion or how nutrients are absorbed, you can take a look at some other tutorials that go more in depth with that. But today we want to identify just the basic structure and function of the digestive system.
So let's take a look at our diagram right here. So this is a diagram of our digestive system. So the main component of our digestive system include the mouth. And the mouth is the site where food enters our body, where it enters the digestive system.
And then within your mouth, the food is chewed, and it's mechanically and chemically broken down. And then you will swallow the food. Food will then move towards the pharynx, which is also known as your throat.
And then from there will move down towards the esophagus. And the esophagus is the tube that connects your mouth and your pharynx to your stomach. And so peristalsis are these wavelike motions that will help push food down the esophagus towards your stomach.
So we have food entering the mouth, moving to the throat, down the esophagus, and then finally it will enter the stomach. So the stomach is the site where food is stored and then food is also mechanically and chemically broken down in the stomach as well.
So we had some mechanical and chemical breakdown that occurred in the mouth and then this will be more extensive in the stomach. So you have different enzymes and gastric juices that are breaking down that food in the stomach.
From there the food is going to move into the small intestine-- labeled here in orange. And the small intestine is the location where most of the nutrients from the food that you eat is absorbed.
After the small intestine, food will then move into the large intestine. And the large intestine is where any remaining nutrients are absorbed and then also water is absorbed from the large intestine as well.
And then from there, once nutrients and water and everything that needs to be absorbed has been absorbed, waste will exit out the end of the large intestine. So waste will be passed. So as I mentioned, it's like one large tube where food is going in, it's going through this whole process, and then waste is being passed out.
So this lesson has been an overview on the structure and function of the digestive system.