Digestive Processes

Lipids and Proteins Lipids Lipids are fats and they are important to our health. When chemically digesting these lipids or fats, these molecules are broken down into smaller ones that can be more readily passed through the digestive system and into the bloodstream. This fat is transformed into triglycerides and can be used by the body for energy at a later time. Lipids like almost all food is first mechanically digested by the mouth.

During this process the first chemical reaction begins when the saliva begins to break down the fat. As the fat is digested, enzymes called lipases within the mouth and stomach break the bonds of the lipid molecules an prepare them for absorption. The gall bladder and pancreas becomes involved in this process as bile salts are released from these organs and secreted in the small intestine. These chemicals signal to further digest the food by breaking down the molecules some more.

Eventually these molecules are absorbed by the cells in the intestinal wall and used by the body for energy. In order for the lipids to be properly digested, they must be emulsified by the bile slats released by the pancreas and gall bladder. The more dispersion of these molecules, the better as the surface tension of the molecules reduces as the surface area exposed to the digestive juices increases.

The bile salts contain sodium glcyocholate and sodium taurocholate which trigger the lowering of the surface tension and properly prepare them for further digestion. At this stage of digestion, the broken down molecules or fatty acids or glycerol is ready to be absorbed into the body. This occurs in the intestines where villi, the finger like projections that are covering the intestinal wall absorb the acids and glycerol into the lymphatic system which in turn delivers hormones to the blood stream.

The most important issues dealing with lipid digestion is ensuing that the fats are soluble and ready to be taken in by the small intestine. After digestion, monoglycerides and fatty acids associate with bile salts and phopholipids to form micelles. Micelles are always breaking down and re-forming, feeding a tiny group of monoglycerides and fatty acids that are in solution. Chylomicrons are lipoproteins, that are designed for the movement of lipids in the circulation. Because they are particles, they are too large to enter typical capillaries.

Instead they enter lacteals, lymphatic capillaries that connect into the center of each villus. Proteins The breakdown of dietary protein by the human digestive system results in producing amino acids, which, in turn allows for the building blocks for essential compounds in your body such as cell proteins, hormones, enzymes and genetic material. The human mouth doesn't have enzymes to digest proteins, so they don't begin digestion until they reach the stomach.

When proteins reach the stomach, the cells produce acid and an enzyme called pepsin, which work in tandem to continually break down the protein into much smaller proteins and some single amino acids. Next these amino acids travel to the small intestine, where they are bombarded with another set of enzymes secreted from the pancreas and intestinal wall cells. These enzymes continue the work of the pepsin enzyme of the stomach, breaking down the proteins into single amino acids.

These amino acids are then transported across the intestinal wall cell and travel through the bloodstream, supplying amino acids to the different.