Once foods are broken down nutrients are absorbed

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Once foods are broken down, nutrients are absorbed into your body through the wall of the small intestine and distributed through the bloodstream. These proteins speed up chemical reactions that turn nutrients into substances that your digestive tract can absorb. Your saliva has digestive enzymes in it. Some of your organs, including your pancreas, gallbladder, and liver, also release them. Digestive enzymes are mostly produced in the
pancreas, stomach, and small intestine. But even your salivary glands produce digestive enzymes to start breaking down food molecules while you are still chewing. - Describe digestive system hormones and the ways they regulate digestive system The major hormones that control digestion are gastrin, secretin, and cholecystokinin (CCK). Gastrin promotes secretion of gastric juice, increases gastric motility, promotes growth of gastric mucosa, constricts lower esophageal sphincter, and relaxes pyloric sphincter. Distension of stomach, partially digested proteins and caffeine in stomach, and high pH of stomach chyme stimulate gastrin secretion by enteroendocrine G cells, located mainly in mucosa of pyloric antrum of stomach. Secretin stimulates secretion of pancreatic juice and bile that are rich in bicarbonate ions. It also inhibits secretion of gastric juice, promotes normal growth and maintenance of pancreas, and enhances effects of CCK. Acidic (high H+ level) chyme that enters small intestine stimulates secretion of secretin by enteroendocrine S cells in the mucosa of duodenum. Cholecystokinin (CCK) Stimulates secretion of pancreatic juice rich in digestive enzymes, causes ejection of bile from gallbladder and opening of sphincter of the hepatopancreatic ampulla (sphincter of Oddi), induces satiety (feeling full to satisfaction). It also Inhibits gastric emptying, promotes normal growth and maintenance of pancreas, enhances effects of secretin. Partially digested proteins (amino acids), triglycerides, and fatty acids that enter small intestine stimulate secretion of CCK by enteroendocrine CCK cells in mucosa of small intestine; CCK is also released in brain. - Describe LDL and HDL in a detail. Make sure that you link the description of these lipoprotein particles to the atherosclerotic disease. Low-density lipoproteins (LDL) are also known as “bad cholesterol.” They carry 75% of total cholesterol in the blood. They deliver cholesterol to cells throughout the body for use in repair of cell membranes and synthesis of steroid hormones and bile salts. High density lipoproteins (HDL) are known as “good cholesterol.” They contain 40-45% proteins, 5-10% triglycerides, 30% phospholipids, and 2-% cholesterol. HDLs prevent accumulation of cholesterol in the blood and are associated with decreased risk of coronary artery disease. The key events in the launch of ASCVD are the retention and accumulation of cholesterol-rich apo B-containing lipoproteins within the arterial intima at sites of predilection for plaque formation. High-density lipoproteins (HDLs) oppose

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