Digestive system and its function How does digestion work - animation Why is digestion important? How does food move through the GI tract? What happens to the digested food molecules? How is the digestive process controlled?
Tell us about yourself Are you primarily a: Healthcare provider in an academic clinic. When chyme from an ingested meal enters the small intestine, acid and partially digested fats and proteins stimulate secretion of cholecystokinin and secretin. As discussed previously, these enteric hormones have important effects on pancreatic exocrine secretion.
They are both also important for secretion and flow of bile:. Physiology of the Hepatic Vascular System. An Irish Gaeilge translation of this page was created by Brian Kiley and is available at Irish translation. A Russian translation of this page was created by Mary Davidson and is available at Russian translation. A Spanish translation of this page was created by Manuel Gomez and is available at Spanish translation.
A Ukrainian translation of this page was created by Olena Chervona and is available at Ukrainian translation. Between meals, bile is stored in the gallbladder and only a small amount of bile flows into the intestine. Bile also becomes more concentrated during this storage process.
Fatty foods that enters the duodenum prompt hormonal and nerve signals that cause the gallbladder to contract. The hormones that control this process are:. Signals also come from the vagus nerve , which extends from the brainstem all the way down to your abdomen. As a result, bile flows into the duodenum and mixes with food, stomach acids, and digestive fluids from the pancreas , which helps the intestines absorb nutrients into the bloodstream.
Most of the bile acids are absorbed through the lower intestine then circulated into the bloodstream and back to the liver. Bile is a liquid produced by your liver and stored in your gallbladder. When prompted by hormones and the vagus nerve, bile is released from your gallbladder into your duodenum and intestines.
Your body then uses it to break down fats, absorb vitamins, and remove wastes that your body doesn't need. Many people are familiar with jaundice , when bilirubin the main pigment in bile accumulates in the bloodstream.
It is common in newborns, who are not always developed enough to remove the pigment from their system. Classic signs include dark urine and yellowing of the skin and eyes. But jaundice can also occur in people of all ages when bile flow from the liver to the duodenum slows or stops for another reason. Known as cholestasis , this can occur as a result of liver, pancreas, or gallbladder disorders, or any damage to bile ducts.
Conditions that can scar or inflame the liver and lead to cholestasis include:. Bile duct damage is generally considered a symptom of chronic hepatitis C. Other conditions that can affect bile production or flow include:.
Your gallbladder is most likely to give you trouble if something like a gallstone blocks bile from flowing through the bile ducts. Treatment may include cholecystectomy , which is surgery to remove the gallbladder. After this procedure, bile gets transferred directly from the liver to the small intestine. The gallbladder is not essential to the process. Bile duct obstruction, due to gallstones or gallbladder cancer, can actually mimic acute viral hepatitis. Ultrasound can be used to rule out the possibility of gallstones or cancer.
Bile reflux is another related condition. It occurs when bile gets backed up in your stomach and esophagus, the tube that connects your mouth and stomach. Bile reflux sometimes happens along with acid reflux.
Unlike acid reflux, dietary or lifestyle changes don't usually improve bile reflux. Treatment involves medications or, in severe cases, surgery. Bile is made of several components, including bile acids, bilirubin, and fats. Fats need more chemical interaction in order to be changed into energy. When you digest fatty food, your gallbladder releases bile. This digestive juice passes down a narrow tube the cystic duct.
It goes straight into the first section of your small intestine, just underneath your stomach the duodenum. There, the strong chemicals go to work. They break down fatty bits into a liquid form that you can digest. Your bile travels down your cystic duct into your small intestine. Then another branch of ductwork, called the pancreatic duct, joins the channel.
The pancreatic duct carries enzymes from your pancreas.
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