What Is The Digestive System - How The Digestive System Works - Digestive System Function

Описание: In this video I discuss how the digestive system works, digestive system functions, and the components of the digestive system. I also discuss the path of food through the digestive system.






Transcript with notes

Bryan here, and in this video we are going to look at the digestive system.

Now let’s take a look at a diagram and we will go through the digestive systems main components. Starting here with the mouth and salivary glands, which lead to the pharynx, or what we call the throat.

Next we have the esophagus here, which connects to the stomach. The liver is here, along with the gallbladder and the pancreas is back here. Down here is the small intestine which has 3 sections, the doudenum, the jejunum, and the ileum. The large intestine is here, and it also has 3 sections, the cecum, colon and rectum, and the anus is here.

Now let’s go through a very basic look at what happens during the digestive process or the path of food, as well as the digestive system functions.

So, food enters the mouth, where we chew it up. The salivary glands produce saliva, which helps lubricate the food. The saliva also contains digestive enzymes that begin breaking down the food. The food is then swallowed through the pharynx or throat, and passes into the esophagus.

From the esophagus, food enters the stomach. Here, food is churned and mixed with gastric juices to form chyme, which is a soupy like mix. The gastric juices include digestive enzymes and hydrochloric acid, which helps breakdown food further, and also kills potentially harmful bacteria.

There is a ring of muscle near the end of the stomach that is called the pyloric sphincter. This muscle opens at intervals to allow small quantities of the chyme to enter into the first part of the small intestine the duodenum. Small quantities are released to avoid overwhelming the small intestines digestive processes.

In the duodenum, the breakdown of food, or chyme continues with the help of enzymes from the pancreas and bile that is produced by the liver and stored in the gallbladder.

The path of food continues into the 2nd section of the small intestine, the jejunum, and folks, this is where the magic happens. The inner lining of the small intestine is covered by tiny finger like projections called villi. These villi give the small intestine a huge surface area to allow for efficient absorption of nutrients.

Nutrients pass into the interior of a villus. Inside each villus is a tiny lymph capillary, and a blood capillary. Here, Glucose and amino acids, or carbohydrates and proteins, as well as other nutrients are absorbed into the blood capillaries, and transported to the liver for processing. Fats are absorbed into the lymph capillary and transported to the liver by way of the lymphatic duct and circulatory system.

Once the breakdown and absorption is complete in the small intestine, the waste product that remains from this process is partially digested, liquefied food. This passes from the last part of the small intestine called the ileum, through the ileocecal valve, into the 1st part of the large intestine called the cecum.

From there, it enters the 2nd part of the large intestine called the colon. Here, sodium, chloride and water are absorbed through the lining of the colon, into the bloodstream, helping convert the liquid food or chyme into semisolid feces. At the end of the colon is the 3rd part of the large intestine, the rectum, which stores feces, and contracts to expel them through the anus. And that completes the journey of food through the digestive system, and how the digestive system functions.

Alright, if you have any questions or comments you can leave them below, if you like the video hit thumbs up, if I just wasted your time hit the thumbs down…til next time, I’m out, see ya.

Timestamps
0:00 Main components of the digestive system
0:40 How food goes through the digestive system
1:53 How nutrients are absorbed
2:37 Waste product development and excretion