(a) Name the main organs of the human digestive system. Also name the associated glands
(b) How do carbohydrates, fats and proteins get digested in human beings ?

Explanation

(i) Carbohydrates : The human saliva contains an enzyme called salivary amylase which digests starch (carbohydrate) present in food into sugar. Thus, the digestion of carbohydrate begins in the mouth itself.
In duodenum, pancreatic juice which contains digestive enzymes like pancreatic amylase, brakes down the starch (Carbohydrate). It is digested in jejunum by intestinal juice.
(ii) Proteins : In stomech, proteins are digested by gastric juice, in duodenum by pacreactiv juice and in jejunum by intestinal juice.
(iii) Fats : In duodenum and jejunum fats are digested by pancreatic juice aided by bile salts. In infants it is digested in stomach.