Digestive System

• DIGESTIVE SYSTEM is a network of organs that help you digest and absorb nutrition from your food.
• The organs that make up your GI tract, in the order that they are connected, include your mouth, esophagus, stomach, small intestine, large intestine and anus.
• Your biliary system includes your liver, gallbladder, pancreas and bile ducts.
• Your digestive system is uniquely constructed to do its job of turning your food into the nutrients and energy you need to survive. And when it’s done with that, it handily packages your solid waste, or stool, for disposal when you have a bowel movement.
• mouth

  Food starts to move through your GI tract when you eat. When you swallow, your tongue pushes the food into your throat. A small flap of tissue, called the epiglottis, folds over your windpipe to prevent choking and the food passes into your esophagus.
• Located in your throat near your trachea (windpipe), the esophagus receives food from your mouth when you swallow. The epiglottis is a small flap that folds over your windpipe as you swallow to prevent you from choking (when food goes into your windpipe). A series of muscular contractions within the esophagus called peristalsis delivers food to your stomach.
• Lower esophageal sphincter

  • When food reaches the end of your esophagus, a ringlike muscle—called the lower esophageal sphincter —relaxes and lets food pass into your stomach. This sphincter usually stays closed to keep what’s in your stomach from flowing back into your esophagus.
• The stomach is a hollow organ, or "container," that holds food while it is being mixed with stomach enzymes. These enzymes continue the process of breaking down food into a usable form. Cells in the lining of your stomach secrete a strong acid and powerful enzymes that are responsible for the breakdown process. When the contents of the stomach are processed enough, they’re released into the small intestine.
• The small intestine, comprised of the duodenum, jejunum, and ileum, is a 22-foot muscular tube that breaks down food using enzymes and bile. Peristalsis moves and mixes the contents. The duodenum initiates breakdown, while the jejunum and ileum absorb nutrients. The contents change from semi-solid to liquid with water, bile, enzymes, and mucus. After nutrient absorption, the liquid moves to the large intestine (colon).
• The pancreas secretes digestive enzymes into the duodenum that break down protein, fats and carbohydrates. The pancreas also makes insulin, passing it directly into the bloodstream. Insulin is the chief hormone in your body for metabolizing sugar.
• The liver's primary digestive role is processing nutrients from the small intestine, aided by bile secretion for fat and vitamin digestion. As the body's chemical factory, it synthesizes essential compounds from absorbed raw materials. Additionally, the liver detoxifies and eliminates harmful chemicals, breaking down and secreting toxic substances, including drugs.
• The gallbladder stores and concentrates bile from the liver, and then releases it into the duodenum in the small intestine to help absorb and digest fats.
• The colon, a 6-foot muscular tube connecting the small intestine to the rectum, processes waste through peristalsis.
• The colon, comprising the cecum, ascending, transverse, descending, and sigmoid colon, transforms stool from liquid to solid by removing water.
• Stool is stored in the sigmoid colon until a daily "mass movement" empties it into the rectum, taking about 36 hours.
• Beneficial bacteria in the colon perform vital functions, including synthesizing vitamins and protecting against harmful bacteria.
• The descending colon empties its contents into the rectum, triggering bowel movements.
• The rectum, an 8-inch chamber connecting the colon to the anus, receives and holds stool. Sensors in the rectum alert the brain when stool is present, and the brain decides whether to release or retain it. If released, sphincters relax, and the rectum contracts for evacuation. If retention is necessary, the sphincter contracts, providing temporary relief from the sensation.
• The anus, the terminal part of the digestive tract, is a 2-inch canal with pelvic floor muscles and two sphincters (internal and external). The upper anus lining detects rectal contents, signaling whether they are liquid, gas, or solid. Sphincter muscles, particularly the internal sphincter, maintain continence, preventing involuntary bowel movements, especially during sleep. The pelvic floor muscle's angle prevents unintended stool passage. The external sphincter allows control and releases stool when at a toilet in response to the urge to go to the bathroom.
• Constipation generally happens when you go poop (have a bowel movement) less frequently than you normally do. When you’re constipated, your poop is often dry and hard and it’s difficult and painful for your poop to pass.
• Diarrhea is when you have loose or watery poop. Diarrhea can be caused by many things, including bacteria, but sometimes the cause is unknown.
• Heartburn is a painful, burning feeling in the middle of your chest. It’s not really in your heart, though. It’s caused by stomach acid rising into your esophagus (reflux), which runs through your chest, close to your heart. Heartburn is an occasional symptom for many people, and a chronic condition for others, occurring frequently. When it’s chronic, you might have GERD (gastroesophageal reflux disease).
• Hemorrhoids, or piles, are a common issue. These swollen veins inside of your rectum or outside of your anus can cause pain, anal itching and rectal bleeding. Symptoms often improve with at-home treatments, but on occasion, people need medical procedures. Eating more fiber can help prevent hemorrhoids.
• Stomach flu, or viral gastroenteritis, is an infection impacting the stomach and intestines. This viral condition induces symptoms like diarrhea, abdominal cramps, and nausea, commonly referred to as a "stomach bug." While the causative agent can be a virus, bacteria, or parasite, the symptoms often overlap, making it challenging to identify the specific pathogen.
• A stomach ulcer, also called a gastric ulcer, is an open sore that develops in your stomach lining. You can also get one in your duodenum, the first part of the small intestine that your stomach feeds into. Duodenal ulcers and stomach ulcers are both types of peptic ulcers. They’re named for pepsin, one of the digestive juices that are found in the stomach and that sometimes leak into the duodenum. These juices are a contributing factor in peptic ulcer disease.
• Gallstones, formed from cholesterol or bilirubin in the gallbladder, vary in size from a grain of sand to a golf ball. Smaller stones are more likely to cause issues, as they can travel and create blockages.