The Physiology of Digestion

The Physiology of Digestion

Bowl of cereal with fruit and grains
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While the terms “anatomy” and “physiology” are often used interchangeably, the two are in fact different. When pertaining to hepatitis and the liver in general, anatomy implies “structure,” whereas physiology infers “function.” When body functions go haywire, it is all simply called “pathology.” Subpar physiology of the digestive system would serve as a forerunner to different ailments that could also affect another region of the body, including that of the liver.

Hepatitis and Physiology: The Way it Works

Proper digestion would lead to proper absorption of the nutrients called for by organs. Foods rich in probiotics or good bacteria, and rich in fiber, are good foods to be taken in order to keep the rivulet of substances in the GI tract to continuously be smooth. If enough nutrients are absorbed and transported to the different systems and organs of the body, the body system will also toil properly and effectively. Hence, it’s very important to have a great digestive health in order to maintain the decent health of the other organs such as the liver. The digestive system runs through sundry physiological processes such as ingestion, digestion, absorption, motility, secretion and excretion. It is necessary to know how these processes take place in the process of the digestive system, in order to understand what goes amiss with a person who bears the brunt of hepatitis.

Hepatitis Physiology Gone Wrong: Constipation and Gallstones

Furthermore, among the most common illnesses winched by shabby digestive health is constipation. Constipation is caused by lack of fiber that helps move the stool travel along the digestive tract. Having constipation also increases that chance of developing diverticular disease.

This disease is caused by diverticula – the swollen pockets that are formed in the large intestine or colon.

Gallstones are also one of the unexceptional ailments related to the digestive system. Gallstones are solid substances that are formed in the gallbladder. These solid substances are made from bile – a fluid excreted by the liver and stored in the gallbladder. The bile is evacuated from the gallbladder when the digestive system needs to digest fatty foods. If too much fatty nosh is ingested, the tendency is to excrete more bile. Irregular bile expulsion could mean gallstones. Hence, this is caused by eating foods that are high in fats and cholesterol, and having not enough of foods that are heaped with fiber.

Hepatitis and Physiology: Ingestion

Ingestion or intake of food is the first process that’s shaped in the digestive system. The digestion process starts as the food enters the mouth, triggering a process called mastication or chewing. Mastication is a mechanical form of digestion, which grinds and crushes the food with the succor of teeth.

This first step of digestion allows the breaking down of food more efficiently for the enzymes. As the food is positioned between the teeth, the cheek and tongue aid for the grinding and crushing process. The salivary amylase is an enzyme achieved in the saliva – a liquid secreted by the salivary glands. This enzyme begins to breakdown the carbohydrates and starch present in the food. The food then becomes a round slurry mass, called bolus. It will enter the pharynx and esophagus, and will travel down the stomach by way of the drudgery of peristalsis.

Hepatitis and Physiology: Digestion

The chemical and mechanical breakdown of food’s large molecules into smaller components is the process done during digestion. It is a form of catabolism, whereas the large molecules of the food go through a metabolic pathway to be able to turn it into smaller units. As the food is being ingested as a large unit of matter, it contains high molecular weight such as protein and starch. These substances will not be able to cross the cell membrane of the intestinal epithelium that covers the gut, or the tube where the food is reassigned to the organs of digestion; hence, these multifaceted molecules need to be degraded into smaller molecules such as glucose and amino acids for it to be utilized.

The hepatitis sufferer may want to note that the stomach secretes gastric juice that activates digestive enzymes – which initiates the digestion of protein existent in food. The gastric acid will then make the ingested proteins become unraveled to let the digestive enzymes break down the chains of amino acid. After around 1-2 hours, the motley of bolus becomes a slimy thick liquid called chyme. The chyme passes into the duodenum to be amalgamated with digestive enzymes secreted by the pancreas, called pancreatic juice, which can digest lipids, proteins, carbohydrates, and nucleic acid. The chyme will then succeed through the small intestine to further breach down fodder. The absorption process takes hold following the full metabolism of the chyme.


Chapman HW, reviewer. Comparative physiology of the vertebrate digestive system. Can Vet J. 1997 Sep; 38(9): 576–577.

Karasov WH, Martínez del Rio C, Caviedes-Vidal E. Ecological physiology of diet and digestive systems. Annu Rev Physiol. 2011;73:69-93.

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