As the content of chyme move into the small intestine, there are some accessory organs in play. I call them accessory organs because the food does not travel through these organs, but they do provide important functions for digestive processes. The first is the liver.
The liver has a multitude of life-necessary functions in our body. But as far as digestion, its big function is making bile that will be used with fat. The bile is used to make bile.
The bile is immediately sent to the gallbladder where it is stored until it is needed. As fat enters the small intestine, a hormone signals to the gallbladder to release the bile. There is a duct that connects with the pancreas and enters into the small intestine.
The next accessory organ is the pancreas, which sits just behind the lower lobe of the stomach. Again, there are many critical functions. has for our body, but with digestion it has two main functions.
The first is to fix a big problem that we have with the stomach contents. Recall that the contents are highly acidic and the small intestine does not have mucus. Therefore, the pancreas secretes bicarbonate in its juices to neutralize the pH of the kind.
The second is to synthesize the enzymes needed to digest carbohydrates, fats, and proteins. As stomach contents enter the small intestine, the pancreas activates and releases the enzymes into the pancreatic juices that also contain the bicarbonate into the duct that carries it into the small intestine. As I mentioned, the stomach contents are slowly squeezed into the small intestine.
At the same time, the contents from the gallbladder and pancreas come together to enter the small intestine. The juices can contain bile for fat, bicarbonate to neutralize acid, and pancreatic enzymes to digest carbohydrates, fats, and proteins. The small intestine has three sections.
The first section is the duodenum and represents the smallest but most active section. The second is the jejunum in the light yellow. The final section is the ileum represented in the darker yellow. The majority of digestion is the duodenum.
occurs in the first part of the small intestine, in the section known as the duodenum. The enzymes, bile, and bicarbonate enter into the duodenum and go right to action right there in the duodenum. Next, we will identify how the three macronutrients are digested in the small intestine. Carbohydrates are the easiest to digest.
The larger starch molecules already began the chemical breakdown in the mouth. Nothing happened to carbs in the stomach. In the small intestine, we are left with partially digested starches and sugars.
The pancreatic enzymes chemically break down the bonds of the remaining carbs. These are broken down into the smallest components, monosaccharides. Protein was denatured in the stomach and had a small amount of enzyme breakdown from pepsin. Since the protein strand is now uncoiled, the enzymes are now in the pancreatic. in the small intestine can easily break the bonds of the protein chains down into the smallest components amino acids.
Fat is a little harder to digest. When fat enters the small intestine it will float because it is hydrophobic. The problem is that the enzymes are down in the watery digestive juices. In order to get the fat down into the water digestive juice we need a compound.
compound that contains both water and fat soluble properties. This is where bile comes in. Bile has properties of both hydrophobic and hydrophilic. In other words, it mixes into both fat and water. Through a process called emulsification, bile is now able to bring the fat into what I call an emulsified fat ball.
Now the enzymes can break the bonds in the fats. They will also need to be broken down into their smallest components, fatty acids.