How is the ileum adapted to its functions?

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Long;  and  narrow;  to  increase  the  surface  area  for  complete  digestion  of  food;  and  maximum absorption  of  digested  food;  highly-coiled;  to  reduce  speed  of  food  flow;  for  maximum digestion;  and  absorption;  presence  of  villi;  and  microvilli;  to  increase  surface  area;  for maximum  absorption;  dense  network  of  capillaries;  to  transport  blood;  for  efficient  transport  of absorbed  food;  presence  of  lacteals;  for  absorption  of  fatty  acids  and  glycerol  molecules; presence  of  enzymes:  Lipase;  for  digestion  of  lipids  into  fatty  acids  and  glycerol;  maltase;  for digestion  of  maltose  to  glucose  molecules;  peptidase;  for  breakdown  of  peptides  into  amino acids;  sucrase;  for  digestion  of  sucrose  into  glucose  and  fructose;  lactase;  for  digestion  of lactose  into  glucose  and  galactose;  goblet  cells;  produce  mucus;  to  lubricate  the  walls  of  the ileum;  for  smooth  flow  of  food;  coats  the  walls  of  ileum  to  prevent  digestion  by  peptidase enzyme;  Max.  20  mks 

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