The human digestive system is a wonderful mechanism that allows us to break food down and use it in order to maintain our organism. When consuming food, our body undergoes a series of biological reactions that lead to the process of digestion and allow us to obtain such essential nutrients as vitamins and minerals. Understanding how the digestive system works will help us enhance our digestion and boost our energy levels.
Components of the Human Digestive System
The human digestive system may be viewed as a linear chain from the entrance to the exit; nevertheless, there are quite a lot of different organs that participate in this chain. Starting from the mouth and ending with the anus, the digestive system involves different mechanisms to break down food into smaller and smaller particles that may be easily absorbed and used further.
The Mouth
Mouth is the place where the digestive process begins as well as where food is first subjected to biological changes. There are several components that perform their functions during digestion in the mouth cavity. First of all, it should be noted that food is ground with the help of teeth; besides, saliva is secreted in the mouth cavity and helps dissolve food particles. There is also the tongue that mixes food with saliva and moves it around the mouth. The tongue consists of structures named papillae.
While chewing food, mechanical digestion occurs. This process means that food is divided into smaller pieces that are easier to digest. Mechanical digestion occurs due to movements of muscles of the tongue as well as grinding with the help of teeth. Food also passes through the esophagus to get to the stomach.
The Esophagus
This is a muscular tube that helps deliver food from the mouth cavity to the stomach. Movement of food to the stomach occurs due to a special process known as peristalsis, i.e., muscle waves. Food becomes slightly wet during passing through this tube as it comes into contact with a small amount of mucus in order to minimize friction.
It is worth saying that esophagus is a very well-developed organ in terms of its adaptation to its function. It is a muscular tube covered with mucus membranes that protect the walls of the tube from the aggressive environment of the stomach. Moreover, there is a sphincter muscle in the esophagus regulating the process of delivering food to the stomach.
The Stomach
This organ is unique in the sense that it continues to break down food into smaller particles. This is a sac-shaped organ covered with a protective layer of mucus membrane that protects it walls from a highly aggressive environment. pH level of the stomach is around 1.5-2.5; this level enables decomposition of proteins and other large particles. Moreover, the stomach produces gastric juice that contains enzymes such as pepsin that divide proteins into peptides and amino acids.
Besides, gastric juice also produces enzymes destroying bacteria. In addition, it stimulates secretion of mucus protecting the walls of the stomach from corrosion caused by a high acidity level.
The Small Intestine
This organ plays a major role as regards nutrient absorption. This muscular tube is relatively long and thin and contains finger-shaped projections known as villi. These protrusions increase the surface area of the organ allowing nutrients to be easily absorbed.
Small intestine is also covered with microscopic structures named microvilli, which also increases the surface area of the organ and provides an additional surface for nutrient binding and absorption. Moreover, these microscopic structures are covered with receptor proteins that bind nutrients.
The Large Intestine
This is the last organ in the digestive system. It has two primary functions related to digestion: absorbing water and eliminating solid residues. Compared to the small intestine, this organ is relatively short and wide. It also has mucus membrane facilitating the process of absorption.
As for the second function of the large intestine, it is to contain microorganisms that are capable of destroying complex carbohydrates and other macromolecules, which the human body cannot digest. They are called gut flora.
Maintenance of a Healthy Digestive System
A healthy digestive system is very important for humans as it ensures proper functioning of the body. Firstly, it allows for efficient absorption of nutrients ensuring appropriate energy level. Secondly, a healthy digestive system prevents different disorders associated with malnutrition.
There are several measures to ensure proper functioning of the digestive system. A balanced diet based on various fruits, vegetables, and whole grain foods ensures good digestive health. Moreover, proper fluid consumption prevents such conditions as constipation.
