Can you explain the digestive system?what happens when food is swallowed from the mouth all the way to where it is stored in the body, and what are the main functions of the different parts of the digestive system??
thx in advanced!
Posted by Death Row
yes, i can explain the digestive system!!
Posted by i love dancing with the stars
it enters your oral cavity, goes down your esophagus into the stomach, leaves the stomach by the pyloric sphincter, starts going down the small intestine which is the duodenum, jejenium, and the iluum, passes the appendex, goes into the cecum into the accending, transverse, and decending colon, then to your sigmoid colon to the rectum and then the anus. hopes this helps!!
Posted by Gina
The bolus (chewed up ball of food) travels down the esophagus and into the stomach. In the stomach, hydrochloric acid breaks down starch, proteins, and lipids into their monomeric forms (mainly glucose, amino acids, and triglycerides). The mixture of food and digestive juices enters the small intestine, where the majority of nutrient and water absorption takes place. In the colon (large intestine), further water absorption occurs, and the fecal matter is formed. Feces is composed mainly of bacteria that inhabit the digestive tract, bile (an emulsifier secreted by the gall bladder which breaks down fat particles), and food matter than cannot be digested such as the gristle of meat. This is excreted though the rectum and anus.
The stomach and intestines have very similar structures, consisting of four layers. The innermost is called the mucosa, which consists of a thin layer of epithelial cells, a layer of connective tissue called the lamina propria which holds the epithelium in place, and a thin layer of smooth muscle called the muscularis mucosae. The mucosa is where nutrient and water absorption occur.
The next layer is the submucosa, which is a layer of connective tissue containing larger blood and lymph vessels than the mucosa. It also contains the submucosal plexus (also called Meissner's plexus), which innervates the epithelium and muscularis mucosae.
The third layer is the muscularis externa. In the intestines, this consists of two layers of smooth muscle; an inner round layer, which constricts the digestive tract when it contracts, and an outer longitudinal layer, which shortens the digestive tract when it contracts. In the stomach, there is a third layer (on the inside) of oblique muscle; contraction of the three layers of smooth muscle in the stomach allows the digesting food to churn and break down more easily. In between the round and longitudinal layers of muscle is the myenteric plexus, which innervates the two (or three) layers of smooth muscle. The submucosal and myenteric plexuses are the two main nerve networks of the enteric nervous system, which coordinates digestive function.
The fourth and outermost layer is the serosa, which is continuous with the peritoneum which lines the abdominal cavity. The peritoneum also forms mesentery, thin sheets of tissue that connect the folds of the small intestine to help hold it in place while it contracts during digestion.
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