Tag: digestive system of human

'Lacrimal gland' is not a salivary gland.

Stenson's duct is associated with 'parotid gland'.

Humans produce between one-fifth and one-third of a gallon (0.75 to 1.5 liters) of saliva every day. However, saliva production mostly takes place while a person is awake. During sleep, saliva production drops to almost nothing. Most of the saliva comes from the glands at the bottom of the mouth, and the rest comes primarily from the parotid glands, near the top back of the mouth.

The rabbit has four major pairs of salivary glands: the parotid, mandibular, sublingual and zygomatic. Amylase and galactosidase are produced in the saliva, which is produced continuously by the mandibular glands and in response to food intake by the others.

Ptyalin is a form of amylase found in saliva of humans. Another name of ptyalin is salivary amylase. It is the most important amylolytic enzyme secreted in mouth (buccal cavity) by the salivary glands. The main function of ptyalin is to catalyze the hydrolysis of starch into maltose and dextrin. 

• Digestion of protein is initiated in the stomach by the enzyme pepsin.
  
• In the small intestine, further digestion is done by trypsin, chymotrypsin, and carboxypeptidase into dipeptidase that releases from the pancreas.
• Dipeptidase are broken into amino acids by intestinal dipeptidase.
  
• These amino acids are absorbed actively by walls of intestine and release in the bloodstream.
• These are utilized by tissues and broken down into carbon dioxide and ammonia.
• Proteins require maximum energy to digest.

So the correct option is 'Peptides are broken down into amino acids by pancreatic carboxypeptidase and intestinal aminopeptidase.'

 Parietal cells of stomach secrets hydrochloric acid which convert inactive pepsinogen to partially active pepsinogen, partially activates pepsinogen then cleaves the peptide from other pepsinogen molecules to form active pepsin which converts protein into proteases and peptides.