In this paper, I will be discussing the stomach. The stomach is found in the top part of our abdomen. The stomach is shaped like a bean or an oblong, hollow oval and is empty inside. There are ridges of muscle tissue called rugae lining the stomach. It is a compartment attached to our esophagus and is where our food travels from our mouth. It goes down the esophagus and empties into the copus, or body, of our stomach. The stomach’s muscles in this area contract which is needed to move the food. The stomach also secretes acid, mucus, and enzymes that play their own roles in the digesting of the food. The gas from the chemicals released are stored in an area called the fundus. Once the food is fully digested, digested, the pyloric sphincter is a muscular valve and it opens to let the food go from the stomach to the the pylorus, which connects the stomach to the small intestine for further distribution. (Organs of the Body)
From the intestines, waste is gotten rid of while the good nutrients and energy is sent out through our bodies where it is needed. The importance of the stomach to the body as a whole is that is breaks down the food we eat and what we drink into nutrients and energy. The nutrients and energy are what any living thing needs in order to thrive, without digesting what we consume, we would die.
There are many parts that make up the stomach. The first part of the stomach is the cardia. It is the part that is near the esophagus and it is made up of cardiac glands that secrete mucus. Next is the fundus, it is located in the arch of the stomach and has gastric glands which release gastric juices that break the food down. Rugae is the walls of the stomach that fold over and help with digestion by expanding to allow more space.
“The wall of stomach, like the other parts of the gastrointestinal tract, consists of four layers, Mucosa, Submucosa, Muscularis, Serosa.” (Saikat R., 2016) The mucosa layer itself is further divided into three layers called surface epithelium, lamina propria, muscularis mucosa. The surface epithelium has gastric glands that make the enzymes that also helps with digestion. Parietal cells, Stem cells, Mucous cells, Chief cells and Enteroendocrine cells are the cells that make up the surface epithelium layer. Parietal cells are the cells that secrete the gastric acid that helps in breaking down the food. The chief cells make digestive juices in the stomach. If an injury is present chief cells become stem cells in order to make repairs. (Science Daily, 2013) Mucous cells secrete an alkaline mucus that protects the epithelium. Enteroendocrine cells are found in the wall of the stomach and secretes hormones which helps with controlling glucose levels, taking in the food, and emptying the stomach.
The lamina propria layer has connective tissue as well as smooth muscle. The cells in this layer are called lymphoid cells. The muscularis mucosa layer is made of smooth muscle and functions as a barrier between mucosa and submucosa. The submucosa layer is thick with connective tissue. There is blood and lymph vessels in this layer. The cells making up this layer are called lymphoid cells, macrophages, and mast cells. Mast cells release chemicals like antihistamines, macrophages eat bacteria, and lymphoid cells are formed from stem cells located in the bone marrow and circulated in the blood through the lymphoid tissue. (Encyclopedia Brittanica) The muscularis layer has multiple layers of fibers that are going in different directions like circular, oblique, and longitudinal. The outside thin layer is called Serosa and is a serous membrane. The organs not be made up of just one cell type because each have a specific function. They work as a group to get the big job of digesting food and liquids done. (Saikat R., 2016)
Cells divide some molecules while building others like fats, proteins, and sugars. These nutrients and energy are what the human body needs to function. We are consumers so we take in food to supply those resources that our body needs. If it weren’t for our stomach’s, we would eventually die because the food we intake would not break down or even know where to go. The waste would just sit inside us with no way of going anywhere, not to cells or exiting the body.
