My Dinner Through The Digestive System

In America, a balanced dinner typically includes ordering pizza from your local pizza shop, chips that have been on the store shelf for too long, a carbonated drink, and lastly, a wonderful chocolate dessert such as brownies or chocolate chips. Although this may taste very good, it is not good for your body. Throughout my childhood, my mom has always made home cooked meals, consisting of a healthy diet. For example, she would make an assortment of recipes using chicken as well as provide a side dish including artichokes or steamed broccoli. Some other types of meals that she would make would include salmon with sweet potatoes and sauteed spinach, steak with homemade mashed potatoes, and orzo salad. These meals are amongst the healthier side of the food spectrum, however, there are always exceptions.

My favorite meal consists of baked salmon, steamed sweet potato with butter and sugar, and sauteed spinach with garlic. The salmon, being the main course, would be considered the fat and protein. The steamed sweet potato, topped with butter and sugar, would be considered a vegetable and consists of Carbohydrates and sugars. Additionally, sauteed spinach with garlic would be a vegetable. This meal consists of Fats, Carbohydrates, Sugars, Proteins, and Vegetables, making it a healthy meal.

The salmon, sweet potatoes, and spinach will first enter the alimentary canal, a long tube that begins at the mouth and ends at the anus. When the mouth receives the salmon, sweet potato, or spinach, it will be tasted and broken down by the teeth as well as lubricated by saliva and swallowed. The salmon will be broken down by the enzyme protease, which breaks down proteins into amino acids. The sweet potato will be broken down by the enzyme Amylase, which breaks down starches and carbohydrates into sugars. The sauteed spinach and garlic (due to the oils from the pan) will be broken down into lipase, which breaks down lipids into glycerol and fatty acids. The teeth break down the food by chewing and grinding known as mastication. Additionally, the tongue is a muscular organ that allows a person to taste the difference between sweet, salty, sour, and bitter sensations. The salmon and sweet potato will taste sweet as the spinach will taste salty. The tongue also assists in the process of chewing food. The three pairs of salivary glands, parotid, sublingual, and submandibular, produce saliva allowing the mouth to be lubricated as well as for the food to be swallowed easier. Additionally, saliva contains an enzyme called salivary amylase. This allows for the process of carbohydrates or starches to be broken down into sugars that will be useful for the body. After the food is chewed and lubricated, it will enter the pharynx. The pharynx is a tube that consists of both air and food. However, my dinner will travel down the esophagus, the food pipe. The esophagus will carry the mixture of food to the stomach. However, in order for my dinner to arrive at the stomach, the esophagus must rely on the involuntary movement of its muscles called peristalsis.

Once the salmon, sweet potato, and spinach have entered the stomach, it will remain there for two to four hours. During this time, the food will turn into a semi fluid material by the gastric juices produced by glands in the stomach which contain enzymes and hydrochloric acid. The hydrochloric acid kills bacteria and activates an enzyme called pepsin. The enzymes in the juices also include lipase, which breaks down the fats and pepsin, which helps with protein digestion.

After the semi fluid salmon, sweet potato, and spinach leave the stomach, it will enter the small intestine. The small intestine consists of three sections: the duodenum, jejunum, and ileum. The duodenum is the first part of the small intestine. It provides for an entryway for bile and pancreatic juice. The jejunum forms the middle section of the small intestine. Lastly, the ileum section which connects with the large intestine. The small intestine also produces intestinal juices which contain enzymes such as maltase, sucrose, and lactase allowing the breakdown of sugars in the sweet potato to occur. The enzymes peptidases (breakdown of proteins, salmon and sweet potato) and lipase (breakdown of fat, salmon) also complete the digestion process in the small intestine. Bile from the liver and gallbladder break down the salmon and sweet potato. While the salmon, sweet potatoes, and spinach are in the small intestine, the digestion process is completed and the nutrients become absorbed in the bloodstream and are ready for use by the body cells. The walls of the small intestine are lined with villi, which have blood capillaries and lacteals. They will then travel to the liver, the largest gland in the body. The liver secretes bile which is used to make fats in the digestive tract. Additionally, it produces heparin which prevents clotting of blood. Lastly, it detoxifies harmful substances such as alcohol. However, the remaining nutrients will flow to the large intestine.

The large intestine is the last part of the alimentary canal. It absorbs water, stores indigestible materials before excretion, and allows for transportation of waste products out of the alimentary canal. The large intestine is divided into many parts. The first part is the cecum and it is connected to the ileum of the small intestine which contains the vermiform and appendix. The next part is the colon which reabsorbs fluids and process waste products ready for excretion. Lastly, the rectum. The rectum acts as a storage area for food that can’t be digested. Lastly, the unwanted fecal material will then exit through the anus.