what is the process of digestion in the stomach?

Answer 1

In humans, digestion begins in the oral cavity where food is chewed (mastication) with the teeth. The process stimulates exocrine glands in the mouth to release digestive enzymes such as salivary amylase, which aid in the breakdown of carbohydrates. Saliva begins the process of chemical catabolism, hydrolysis. The bolus is pushed down by the movement called peristalsis, which is an involuntary wave-like contraction of smooth muscle tissue, characteristic of the digestive system. When swallowed, the food enters the pharynx, which makes special adaptations to prevent choking or aspiration when food is swallowed.

The food enters the stomach upon passage through the cardiac sphincter. In the stomach, food is further broken apart through a process of heuristic churning and is thoroughly mixed with a digestive fluid, composed chiefly of hydrochloric acid, and other digestive enzymes to further denature proteins. The parietal cells of the stomach also secrete a compound, intrinsic factor which is essential in the absorption of vitamin B-12. As the acidic level changes in the small intestines, more enzymes are activated to split apart the molecular structure of the various nutrients so they may be absorbed into the circulatory or lymphatic systems.

After being processed in the stomach, food is passed to the small intestine via the pyloric sphincter. This is where most of the digestive process occurs as chyme enters the first 10 inches of the small intestine, the duodenum.

Here it is further mixed with 3 different liquids:
1)bile
2) pancreatic juice and enzymes
3) intestinal enzymes of the alkaline mucosal membranes.
The enzymes include:
-maltase
-lactase
-sucrase, to process sugars.
Trypsin and chymotrypsin are other enzymes added in the small intestine. Most nutrient absorption takes place in the small intestine. The nutrients pass through the small intestine's wall, which contains small, finger-like structures called villi. The blood, which has absorbed nutrients, is carried away from the small intestine via the hepatic portal vein and goes to the liver for filtering, removal of toxins, and nutrient processing. The primary activity here is regulation of blood glucose levels through a process of temporary storage of excess glucose that is converted in the liver to glycogen in direct response to the hormone insulin.

After going through the small intestine, the food then goes to the large intestine.
The large intestine has 3 parts:
-the cecum
-the colon
-the rectum.
In the large intestine, water is reabsorbed, and the foods that cannot go through the villi, such as dietary fibre, can be stored in large intestine. Fibre helps to keep the food moving through the G.I. tract. The food that cannot be broken down is called faeces. Faeces are stored in the rectum until they are expelled through the anus.

Answer 2

The food enters the stomach upon passage through the cardiac sphincter. In the stomach, food is further broken apart through a process of heuristic churning and is thoroughly mixed with a digestive fluid, composed chiefly of hydrochloric acid, and other digestive enzymes to further denature proteins. The parietal cells of the stomach also secrete a compound, intrinsic factor which is essential in the absorption of vitamin B-12. As the acidic level changes in the small intestines, more enzymes are activated to split apart the molecular structure of the various nutrients so they may be absorbed into the circulatory or lymphatic systems.

the hormone Gastrin - is in the stomach and stimulates the gastric glands to secrete pepsinogen and hydrochloric acid. Secretion of gastrin is stimulated by food arriving in stomach. The secretion is inhibited by low pH

The high acid content of the stomach inhibits the enzyme activity for carbohydrate digestion n it is suspended in the stomach.

The gastric lipase is of little importance is active in the stomach and can Most fat digestion begins in the duodenum. so the breakdown of complex fat globules occurs in the duodenum as the contents of the pancreatic duct empty into the lumen.

refer to a v. good ANIMATION IN:

http://www.maxanim.com/physiology/Gastric%20Secretion/Gastric%20Secretion.htm

Now give me my 10 pts!

.....just joking!

Answer 3

Digestion?

Answer 4

Stomach is like a huge storage bag, in which food is batch processed, using stomach acids, enzymes, bacteria...and then realised to small intestine, for further processing and extracting of nutrients.

Answer 5

I cannot explain the process, but if you want info try:


http://www.medicinenet.com/digestion/focus.htm

Answer 6

fat and protein digest slower than carbs, calories through carbs are usually absorbed pretty quickly was they hit your stomach while carbs and protein take awhile

Answer 7

Hi there !

sorry..! Beyond the scope of this column...
please refer the "text book of Physiology" by Guyton...or Reddy..!

but we should know.."what to ask and what NOT to ask...right ????

best wishes...