Gastric Juice is the mixture of secretions from all the glands present in the stomach. The production of gastric juices is limited while a person is asleep, but production resumes upon awakening. It is most helpful in the digestion of food. It consists of Enzymes present in the stomach. It helps in absorbing the food in the body very easily. They are secreted by glands lining the stomach and function to break down food in the stomach and kill bacteria.
Gastric Juice is a skinny dilute acid digestive fluid secreted by glands in the mucous membrane of the stomach. Simply this Juice is the combination of secretions from all the glands present in the stomach. These juices are in the stomach, and their job is to start breaking down food after you’ve swallowed it so it can be digested. As soon as you put food into your mouth your stomach begins releasing gastric juices.
Gastric acid is a colorless, watery, acidic, digestive fluid produced in the stomach. Generally, the gastric glands are of 3 types – cardiac, fundic and pyloric, named according to the part of the stomach they are present in. This liquid combination will facilitate dissolve food once it reaches the stomach and the procedure of digestion begins. These glands contain three kinds of cells – Cheif cell, Oxyntic Cell and the neck cell which are accountable for the secretion of the gastric juice.
Basic Functions of Gastric Juice –
- Presence of HCL makes the juice antiseptic, killing almost all the germs entering with food
- Pepsinogens are converted to pepsins with the help of HCL and help in protein digestion
- Iron absorption
- Gastric lipase helps in lipid digestion.
- Gastric lipase helps in lipid digestion and most helpful in digestion of food.
- Gastric Juice consists of Enzymes present in the stomach.
- They help in absorbing the food in the body very easily.
Fig: Gastric Juice
(1) Digestive functions –
It helps in digestion by enzymes –
Protein → by pepsinogen
Fat → by Gastric lipase
Milk → by Renin.
(2) Excretory function – Heavy metals, toxins, certain alkaloids are excreted by Gastric Juice.
(3) Hemopoietic function –
The intrinsic factor of the castle of gastric juice helps in Vit B12 absorption from the gut which is essential for RBC maturation.
(4) The function of HCl/ Gastric Juice
- Gastric HCl converts inactive pepsinogen into active pepsin.
- Gastric HCl acts as an antiseptic agent against bacteria.
- It hydrolyzes all food stuff.
- It keeps the iron in the ferrous state for absorption.
- Pepsinogen digests protein up to the stage of peptone due to the presence of gastric HCl.
- It provides a suitable environment for the action of an engine.
- It maintains a proper environment for gastric emptying.
- It converts collagen protein into gelatin.
- It hydrolyzes cane sugar to glucose and fructose.
- It helps in the dissolution of the protoplasmic covering of the fat globules.
(5) Lubricating imitator – The musin of gastric juice lubricates irritant food staffs.
(6) Protection of stomach – The mucin protects the gastric mucosa from HCl. Thus it is not self-digested.
(7) Acid-base regulation – It is responsible for the alkaline tide of blood, during secretion of HCl.
In chemical terms, it is an acid solution with a pH of 1 to 2 in the stomach lumen, consisting mostly of hydrochloric acid (HCl) (around 0.5%, or 5000 parts per million), and huge quantities of potassium chloride (KCl) and sodium chloride (NaCl).