Yes
Animals with a complete digestive system are those in which the digestive tract has two openings, a mouth and an anus (including all other animal phyla, with the exception of poriferans, which do not have any digestive tract). In animals with incomplete digestive tracts, digestion is mixed. The other adnexal gland of the digestive system is the pancreas. This organ produces the digestive enzymes that digest proteins (proteases), lipids (lipases) and carbohydrates (pancreatic amylases). Other buffers perform a more minor role than the carbonic-acid-bicarbonate buffer in regulating the pH of the blood. The phosphate buffer consists of phosphoric acid (H 3 PO 4) in equilibrium with dihydrogen phosphate ion (H 2 PO 4 -) and H + . As shown in Equation 11, the pH of the buffered solution (i.e., the blood) is dependent only on the ratio of the amount of CO 2 present in the blood to the amount of HCO 3 (bicarbonate ion) present in the blood (at a given temperature, so that pK remains constant). In the human digestive system, the main sites of digestion are the oral cavity, the stomach, and the small intestine. Digestive enzymes are secreted by different exocrine glands including: 1  Salivary glands. 2  Secretory cells in the stomach.  1 Release of water, acids, enzymes, and buffers by the digestive tract and by the accessory organs into the lumen of the digestive tract. 2  Absorption. 3  Movement of small organic molecules, electrolytes, vitamins, and water across the digestive epithelium and into the blood and lymph. Gastrointestinal (GI) tract (also called alimentary canal or digestive tract). 1  The GI tract is a continuous tube running from the mouth to the anus. 2  It includes the following organs: 3  mouth. 4  pharynx. 5  esophagus. 6  stomach. 7  small intestine. 8  large Acid-base buffers confer resistance to a change in the pH of a solution when hydrogen ions (protons) or hydroxide ions are added or removed. An acid-base buffer typically consists of a weak acid, and its conjugate base (salt) (see Equations 2-4 in the blue box, below). As shown in Equation 11, the pH of the buffered solution (i.e., the blood) is dependent only on the ratio of the amount of CO 2 present in the blood to the amount of HCO 3 (bicarbonate ion) present in the blood (at a given temperature, so that pK remains constant). Titration Curve for the Bicarbonate-Buffer System. It is possible to plot a titration curve for this buffer system, just as you did for your solution in the acid-base-equilibria experiment. In this plot, the vertical axis shows the pH of the buffered solution (in this case, the blood). As shown in Equation 11, the pH of the buffered solution (i.e., the blood) is dependent only on the ratio of the amount of CO 2 present in the blood to the amount of HCO 3 (bicarbonate ion) present in the blood (at a given temperature, so that pK remains constant). Digestive enzymes are produced by the digestive tract and by the pancreas. In addition the liver produces bile, an emulsifier that plays a role in the digestion of fats. Bile, which is stored in the gallbladder, enters the small intestine along with the pancreatic enzymes.  The mucous membrane-and smooth muscle-lined tube of the digestive system through which food passes, in which digestion takes place, and from which wastes are eliminated; it extends from the mouth to the anus and includes the pharynx, esophagus, stomach, and small and large intestines. aka-digestive tract, gut tube. The process by which food is converted into nutrient molecules which can be absorbed and assimilated by the body; it is accomplished in the digestive system by the mechanical and enzymatic breakdown of foods into simpler chemical compounds. The digestive tractconsists of the oral cavity, pharynx, esophagus,stomach, small intestine, and large intestine. Mostof the absorptive functions of the digestive systemoccur in the small intestine, with smaller amountsin the stomach and large intestine. The pancreassecretes enzymes and buffers important to thedigestion of proteins, carbohydrates, and lipids.The activities of the digestive system are con-trolled through a combination of local reflexes,autonomic innervation, and the release of gastroin-testinal hormones such as gastrin, secretin, and cholecystokinin.
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do buffers exist in digestive system