PP 2

Chemical Digestion  All large molecules are broken down into their simplest forms:  Carbohydrates -> sugar  Protein -> Amino Acids  Fats -> Fatty acids / glycerol  For absorption / assimilation as the simplified molecules are soluble and are easy to absorbe

Enzymes in the alimentary canal Where enzyme is found What the enzyme is Substrate (what it “works on”) End product Mouth & Pancreas AmylaseCarbohydrate (starch) maltose Small intestinemaltasemaltoseglucose StomachpepsinproteinPolypeptides (smaller molecules of protein) Small intestine (duodenum) (from pancreas) Protease (trypsin) Poly peptideAmino acids Small intestine (duodenum(from pancreas) lipasefatsFatty acids + glycerol

villi  Surface area of the villi – 1. Helps speed up rate of absorption 2. Thin walls => only for short distance for digested food to go before it gets to the blood or lymph Capillary absorb: sugar / a. a. / vitamins / inorganic ions / water Lacteal absorb: fatty acids / glycerol

More on the liver  Glucose is absorbed into the liver -> converted to glycogen is not used right away -> for long term storage into fat.  Fat can be broken down into glycogen and then glucose for the body’s use.

 Deamination – removal of the nitrogen containing parts of the amino acids to form urea. It is followed by release of energy from the remainder of the amino acids