GIT AND LIVER SECRETIONS
Secretion Important constituents Function
1. Saliva Salivary amylase, Salivary amylase acts on
750-1000 ml of maltose, (lysozyme, cooked starch and
saliva is secreted / mucin, lingual lipase etc. converts it into maltos.
day Lingual lipase secreted
from lingual glands is a fat
splitting enzyme. It
convert s triglycerides
into fatty acids and 1,2
diacylglycerol .
Mucin lubricates bolus
and facilitates swallowing
Lysozyme has
antibacterial action
2.Gastric Juice •Pepsin,Rennin.secreted The HCI in the gastric juice
o Secreted by chief by chief cells or destroys many types of
cells and parietal pepsinogen cells bacteria in the food.
cells of gastric • Hcl and intrinsic IF is necessary for
glands factor (IF) are secreted absorption of vitamin B12
o 1200-1500 ml by parietal or oxyntic or extrinsic factor
/day Acidic in cells Absence of IF can lead to
nature. PH is 1.0- Gastric lipase (a pernicious anemia
2.0 weak lipolytic Inactive Pepsinogen is
enzyme than converted into active
pancreatic lipase), pepsin in acid medium in
, GIT AND LIVER SECRETIONS
gelatinase other presence of HCL. Pepsin
enzymes. acts on proteins and
converts them into
peptones and
polypeptides. It also
causes curdling and
digestion of milk
Rennin is a milk-curdling
enzyme. It is present only
in animals and is absent in
man.
3. Pancreatic Juice Pancreatic juice The inactive trypsinogen
500-800 ml/day contains. 99.5% of converted into active Trypsin
Alkaline in nature with water and 0.5% of solids by enterokinase of
a pH of 8.0 to 8.3. Proteolytic Enzymes duodenum and by
Trypsin autocatalytic action
Chymotrypsin Trypsin is most powerful
Carboxypeptidase protein splitting enzyme. By
Elastase means of hydrolysis, it
Nuclease converts proteins into
Collagenase proteases and polypeptides.
Lipolytic enzymes Trypsin also converts
chymotrypsinogen into
Pancreatic lipase chymotrypsin, proelastase
Phospholipase into elastase and procolipase
Amylolytic enzyme into colipase
Secretion Important constituents Function
1. Saliva Salivary amylase, Salivary amylase acts on
750-1000 ml of maltose, (lysozyme, cooked starch and
saliva is secreted / mucin, lingual lipase etc. converts it into maltos.
day Lingual lipase secreted
from lingual glands is a fat
splitting enzyme. It
convert s triglycerides
into fatty acids and 1,2
diacylglycerol .
Mucin lubricates bolus
and facilitates swallowing
Lysozyme has
antibacterial action
2.Gastric Juice •Pepsin,Rennin.secreted The HCI in the gastric juice
o Secreted by chief by chief cells or destroys many types of
cells and parietal pepsinogen cells bacteria in the food.
cells of gastric • Hcl and intrinsic IF is necessary for
glands factor (IF) are secreted absorption of vitamin B12
o 1200-1500 ml by parietal or oxyntic or extrinsic factor
/day Acidic in cells Absence of IF can lead to
nature. PH is 1.0- Gastric lipase (a pernicious anemia
2.0 weak lipolytic Inactive Pepsinogen is
enzyme than converted into active
pancreatic lipase), pepsin in acid medium in
, GIT AND LIVER SECRETIONS
gelatinase other presence of HCL. Pepsin
enzymes. acts on proteins and
converts them into
peptones and
polypeptides. It also
causes curdling and
digestion of milk
Rennin is a milk-curdling
enzyme. It is present only
in animals and is absent in
man.
3. Pancreatic Juice Pancreatic juice The inactive trypsinogen
500-800 ml/day contains. 99.5% of converted into active Trypsin
Alkaline in nature with water and 0.5% of solids by enterokinase of
a pH of 8.0 to 8.3. Proteolytic Enzymes duodenum and by
Trypsin autocatalytic action
Chymotrypsin Trypsin is most powerful
Carboxypeptidase protein splitting enzyme. By
Elastase means of hydrolysis, it
Nuclease converts proteins into
Collagenase proteases and polypeptides.
Lipolytic enzymes Trypsin also converts
chymotrypsinogen into
Pancreatic lipase chymotrypsin, proelastase
Phospholipase into elastase and procolipase
Amylolytic enzyme into colipase
