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Title: Describe the pathways of digestion on a cellular level Post by: datty117 on Sep 10, 2012 I have a very heavily weighted question for my bio-chem class. We have to discribe the pathways of digestion on a cellular leavel. For example glycolisis....any help would be AWSOME.
Title: Describe the pathways of digestion on a cellular level Post by: julesarth on Sep 10, 2012 First identify the main nutrients in a turkey sandwich.
Carbohydrates Proteins Vitamins and Minerals (Negligible) Fibre Now, write down the digestion pathway for each. Title: Describe the pathways of digestion on a cellular level Post by: tommyt_ on Sep 10, 2012 Digestion starts in the mouth. Mechanical breaking of food in smaller pieces and mixed with saliva.This increases surface area for enzyme action.
Saliva contains the first digestive enzyme, amylase. This will start hydrolysing starch into smaller chains by breaking the 1,4 glycosidic bonds between a-glucose molecules.Food does not remain long enough in the mouth ,therefore chemical digestion is limited. The food is swallowed and reaches the stomach.Hydrochloric acid is secreted which activates pepsinogen into the active form ,pepsin. This enzyme is a protease and will start hydrolysing proteins into smaller polypeptide chains. Some of the micture is then allowed to enter the duodenum( first 20cm of the small instestine) where sodium hydrogen carbonate is secreted from the pancreas and neutrializes the acid. Also pancreas secrets pancreatic juice containing trypsin(protease),amylase,maltase,lactase and sucrase(all of which are carbohydrases) Trypsin will break all the polypeptides into amino acids by hydrolyzing the peptide bonds and the amylase and maltase will break all starch down to glucose molecules. In the ileum all the products are absorbed. |