What are the organs of the digestive system
The various types of digestive glands present in mammals are salivary glands,gastric glands, intestinal glands,pancreas and liver.The digestive glands secrete digestive juices.Parasympathetic nervous system increases the secretion of digestive juice whereas sympathetic nervous system decreases it.
The three pairs of salivary glands present in humans are as follows-
One-pair ,largest salivary gland present below pinna.A stenson's duct arises from each gland ,opening in vestibule between the 2nd molar teeth of upper jaw and cheeks.Parotid glands secrete enzymes. Viral infection of parotid glands causes"Mumps"(by paramyxo virus).
One-pair,present at the junction of upper and lower jaw in cheek region. A wharton's duct arises from each gland and opens on lower jaw. These are seromucous glands.
One-pair,present in the floor of buccopharyngeal cavity. These are mucous glands 6-8 ducts,called ducts of rivinus or Bartholin's duct arises from these glands and opens below tongue on the floor of buccopharyngeal cavity.
Saliva/ Salivary juice:
The secretion of salivary glands is called saliva or salivary juice.Some of the characteristics are as follows-
- Chemical nature:Slightly acidic.
- Control of secretion:
- Chemical composition:
Autonomic reflex(parasympathetic nervous system increases salivation while sympathetic nervous system inhibit secretion.)
Water(99.5%), mucous(acts as lubricant), salts(NaCl,NaHCO3 etc.) ,enzymes (ptyalin,lysozyme)etc.
what is the function of the digestive system
Salivary juice and its enzymes-
- Makes the medium slightly acidic for the action of its enzyme.
- Help in taste detection,deglutition, speaking etc.