Skip to content
Related Articles

Related Articles

Human Digestive System – Anatomy, Functions and Diseases

View Discussion
Improve Article
Save Article
  • Last Updated : 14 Jul, 2022
View Discussion
Improve Article
Save Article

The related digestive system is comprised of the gastrointestinal system and different organs that help the body separate and assimilate food. It is a long, winding cylinder that beginnings at the mouth and go through the throat, stomach, small digestive tract, internal organ, and rear end.

The stomach-related framework separates food into supplements like starches, fats, and proteins. They can then be retained in the circulatory system so the body can involve them for energy, development, and fix. Unused materials are disposed of as defecation (crap). Different organs that structure some portion of the stomach-related framework are the pancreas, liver, and gallbladder.

Anatomy of  Digestive System

Every organ of the stomach-related framework plays a significant part in absorption.


The mouth, or oral hole, is the initial segment of the intestinal system. It is adjusted to get food by ingestion, break it into little particles by rumination, and blend it in with spit. The lips, cheeks, and sense of taste structure the limits. The oral cavity contains the teeth and tongue and gets the discharges from the salivary organs.


Food begins to travel through your GI plot when you eat. At the point when you swallow, your tongue drives the food into your throat. A little fold of tissue, called the epiglottis, folds over your windpipe to forestall gagging and the food passes into your throat.

Lips and Cheeks 

The lips and cheeks assist in withholding food in the mouth and saving it set up for biting. They are likewise utilized in the development of words for discourse. The lips contain various tactile receptors that are valuable for passing judgment on the temperature and surface of food varieties.

Sense of taste 

The sense of taste is the top of the oral hole. It isolates the oral hole from the nasal cavity. The front part, the hard sense of taste, is upheld by bone. The back segment, the delicate sense of taste, is skeletal muscle and connective tissue. Posteriorly, the delicate sense of taste closes in a projection called the uvula. During gulping, the delicate sense of taste and uvula move up to coordinate food away from the nasal hole and into the oropharynx.


The tongue controls food in the mouth and is utilized in discourse. The surface is covered with papillae that give grating and contain the taste buds. At the point when somebody eats, the teeth bite food into tiny pieces. Organs in the cheeks and under the tongue produce spit that covers the food, making it simpler to be bitten and gulped. Spit likewise contains proteins that begin to process the carbs in food.


The human mouth has three fundamental sorts of teeth: incisors, canines, and molars. Teeth are like bones, however, they are significantly more grounded. They have four tissues: polish, dentin, cementum, and mash. The first, polish, is the piece of the tooth you’re cleaning when you clean your teeth. Polish, a hard tissue, is around 95% mineral. Under this hard external covering, the dentin associates with the nerves in your tooth, and the cementum covers the tooth roots. The mash in the middle contains your tooth all’s nerves, veins, and connective tissue.


  • Eat a solid eating regimen wealthy in protein, leafy foods, calcium, and entire grains.
  • Limit eating and drinking between feasts.
  • Limit sweet food varieties and refreshments.
  • Clean your teeth and tongue two times per day with fluoride toothpaste, and floss one time per day.

Salivary Gland

  • The primary capability of spit are:
  • Helps in processing
  • Helps biting and gulping.
  • Greasing up impact: saturates within the mouth and makes smoother discourse.
  • Dissolvable impact: breaks down food and permits the tongue to taste food.


The throat is the solid cylinder that conveys food from the mouth to the stomach after it is gulped. A ring of muscle toward the finish of the throat unwinds to give food access to the stomach and agreements to forestall stomach contents from getting away from back up the throat.


The stomach is a solid organ situated on the left half of the upper mid-region. The stomach gets food from the throat. As food arrives at the finish of the throat, it enters the stomach through a strong valve called the lower esophageal sphincter.

The stomach secretes corrosive compounds that digest food. Edges of muscle tissue called rugae line the stomach. The stomach muscles contract intermittently, agitating food to improve absorption. The pyloric sphincter is a solid valve that opens to permit food to pass from the stomach to the small digestive tract.

The stomach wall produces gastric juice (hydrochloric corrosive and chemicals) that digests proteins. The stomach behaves like a substantial blender, beating and blending food in with gastric juice to frame chyme — a thick, soupy fluid.

  • The stomach is a sack-like muscle organ situated straightforwardly underneath the liver on the upper-left half of the mid-region.
  • The stomach’s primary occupation is to store and process the food and drink we take during our feasts.
  • It produces hydrochloric corrosive chemicals that guide the processing of food and other unfamiliar particles like microbes.
  • This corrosive delivery can make stomach ulcers, in any case, the corrosive doesn’t consume the stomach on the grounds that the stomach lining is safeguarded by tacky bodily fluid, which shields the stomach lining from the corrosive used in assimilation.

Gastric glands 

The gastric organs are cylinder-like, expanded structures that are available at the internal coating of the stomach. These organs are the fundamental secretory unit of the stomach-related framework and are made out of different cell parts which carry out specific explicit roles. These organs start at the kickoff of the stomach’s lumen, the gastric pits, which itself is available in the gastric mucosa of the stomach. The gastric pit has pale-staining mucous beads because of the presence of mucous-discharging cells.

Types of gastric glands

Cardiovascular Glands 

These organs are found near the heart hole. They ordinarily contain cardiovascular organs. Likewise, they are nearly not many in number and are situated in the mucosa shallowly. These are by and large of two sorts, which are the basic rounded (like those of pyloric closures) and short ducted, and the compound racemose looking like the duodenal organs. Their primary capability in the stomach-related framework is to discharge bodily fluid.

Fundic Glands 

These organs are situated in the fundus or body of the stomach. They are straight, equal, tube-like designs. It has been seen that at least two of such cylinders open into a typical pipe. Additionally, these cylinders are all things considered one-6th the length of the whole organ. These organs are a lot more limited than the pyloric organs. These organs are lined by columnar epithelium. Their fundamental capability in the stomach-related framework is to deliver stomach-related chemicals.

Pyloric Glands 

These organs are the endocrine organs situated in the antrum, known as the pyloric piece of the stomach. They comprise of a few short, wavy shut tubes which open into a typical conduit. These cylinders are by and large a portion of the length of the whole pipe. The channel is generally lined by columnar cells and the cylinders by short, granular cubical cells. The fundamental capability of these organs is to emit gastrin (delivered by G cells) and bodily fluid.

The bodily fluid which is delivered by the Cardiac organs and the Pyloric organs covers the stomach, weakens the acids and catalysts, and thus safeguards the throat and the duodenum from self-absorption

Small Intestine

Bile from the gallbladder and catalysts in stomach-related juices from the pancreas void into the upper part of the small digestive tract and help to separate protein into amino acids and fat into unsaturated fats. These more modest particles, alongside sugars, nutrients and minerals, are ingested into the circulatory system through the mass of the small digestive tract.

It is called little since it is around 3.5cm in width, yet giving heaps of region to absorption is around 5m long. A large portion of the substance processing of proteins, fats, and starches is finished in the small digestive system.


Anatomy of the Small Intestine 

 The small digestive tract is partitioned into the duodenum, jejunum, and ileum. Together these can stretch out up to six meters long. Every one of the three sections is covered with the more prominent omentum anteriorly. The duodenum has both intraperitoneal and retroperitoneal parts, while the jejunum and ileum are totally intraperitoneal organs. As the small digestive system is the principal site for the last phases of food processing and its retention, its gross and microanatomy are acclimated to that capability.


The duodenum by definition is the initial segment of the small digestive tract. It stretches out from the pyloric sphincter of the stomach, folds over the top of the pancreas in a C-shape, and finishes at duodenojejunal flexure. This flexure is joined to the back stomach wall by a peritoneal overlap called the suspensory muscle (tendon) of the duodenum, likewise called the tendon of Treitz. The duodenum has four sections: predominant (duodenal bulb/ampulla), plummeting, flat, and climbing. Among a few elements of the duodenum, we’ll list the two generally significant:

The predominant part (duodenal bulb/ampulla) is the just intraperitoneal part, as the hepatoduodenal tendon and more noteworthy omentum append to it.
The dropping piece of the duodenum has an opening called the major duodenal papilla (tubercle of Vater). The papilla contains the hepatopancreatic sphincter (sphincter of Oddi, Glissons’ sphincter) which directs the purging of the bile from the hepatopancreatic ampulla.


The jejunum is the second piece of the small digestive system. It starts at the duodenojejunal flexure and is tracked down in the upper left quadrant of the midsection. The jejunum is completely intraperitoneal as the mesentery appropriate connects it to the back stomach wall.

There is no unmistakable line of division between the jejunum and ileum, yet there are a few physical and histological contrasts that recognize them:

  • The jejunum addresses the proximal two-fifths of the jejunum-ileum continuum
  • The mass of the jejunum is thicker and its lumen is more extensive than in ileum
  • The jejunum contains more unmistakable round folds of Kerckring.


The ileum is the last and longest piece of the small digestive system. It is found in the lower right quadrant of the midsection, albeit the terminal ileum can stretch out into the pelvic hole. The ileum ends at the ileal opening (ileocecal intersection) where the cecum of the digestive organ starts.

At the ileocecal intersection, the lamina muscularis of the ileum juts into the lumen of the cecum framing a design called the ileocecal overlap. These solid strands structure a strong ring inside the crease called the ileocecal sphincter which controls the exhausting of ileal content into the internal organ.

Round folds(valves of Kerckring, plicae circulares) are the cross-over folds of mucosa tracked down transcendently in the distal duodenum and proximal jejunum
Gastrointestinal villi are fingerlike augmentations of digestive mucosa which project into the lumen of the small digestive tract. Between the villi are gastrointestinal organs (graves of Lieberkuhn) which discharge gastrointestinal juice wealthy in stomach-related proteins.
Microvilli are projections tracked down on the apical surface of each gastrointestinal cell (enterocyte).

Importance of villi 

The villi assume a part in the processing, they likewise are fundamental for the retention of processed supplements. The cells of the villi and one more piece of the small digestive tract, known as the sepulchers, transport food from the gastrointestinal system into the circulatory system, where they can be utilized by the body. The villi help in retention by expanding the surface region of the digestive tract and contain particular cells which transport various kinds of supplements into the blood.

Anything that causes aggravation of the villi in the small digestive tract can influence processing and retention. One conspicuous reason for villi harm is celiac sickness, a problem made by a resistant response to gluten. At the point when individuals with celiac illness eat gluten, the aggravation dulls the villi, making them unfit to partake really in the breakdown and retention of supplements. Different circumstances, like Crohn’s illness, can likewise influence the small digestive system and lead to the malabsorption of supplements.

 Large  Intestine 

The coating of the digestive organ retains water, mineral salts, and nutrients. Undigested fiber is blended in with bodily fluid and microscopic organisms — which halfway separate the fiber — to support the cells of the digestive organ wall thus assisting with keeping the internal organ solid. Dung is framed and put away in the last piece of the digestive organ (the rectum) prior to being dropped off the body through the rear end.


The lower end of your internal organ, the rectum, stores stool until it pushes stool out of your butt during defecation.

The rectum is the last stop before the dung is discharged out of the human body through the butt-centric trench. The electrolytes, for example, sodium, potassium, and chloride are ingested and the unpalatable food fixings are deteriorated by anaerobic microorganisms, like the colon. The stool is thickened by the retention of water and blended in with bodily fluid.
Likewise, the rectum is important for the moderation organ and assumes a key part in the poop component. On the off chance that the stool enters the rectal ampulla (that is ordinarily vacant) it is enlisted by the stretch receptors. That data is moved to the focal sensory system producing the inclination to crap. The expanded strain in the ampulla prompts a more noteworthy unwinding of the compulsory smooth corrugator cutis ani muscle and sphincter ani internus muscle.

Controlling of Digestive System 

Your hormones and nerves cooperate to assist with controlling the stomach-related process. Signals stream inside your GI lot and this way and that from your GI parcel to your mind.


Cells covering your stomach and small digestive system make and deliver chemicals that control how your stomach-related framework functions. These chemicals let your body know when to make stomach-related squeezes and convey messages to your mind that you are eager or full. Your pancreas likewise makes chemicals that mean quite a bit to process.


You have nerves that associate your focal sensory system — your cerebrum and spinal line — to your stomach-related framework and control a few stomach-related capabilities. For instance, when you see or smell food, your mind conveys a message that makes your salivary organs “make your mouth water” to set you up to eat.

You likewise have an intestinal sensory system (ENS) — nerves inside the walls of your GI parcel. At the point when food extends the walls of your GI plot, the nerves of your ENS discharge various substances that accelerate or postpone the development of food and the creation of stomach-related juices. The nerves convey messages to control the activities of your stomach muscles to contract and unwind to push food through your digestive organ.

Diseases of the Digestive System


While it’s normal for individuals to encounter indigestion and acid reflux sometimes, having side effects that influence your everyday existence or occur something like two times every week could be an indication of GERD, a constant stomach-related sickness. Tireless acid reflux, terrible breath, tooth disintegration, sickness, torment in your chest or upper piece of your midsection, or experience difficulty gulping or breathing.

Gall Stone

Gallstones are hard stores that structure in your gallbladder — a little, pear-molded sac that stores and secretes bile for processing. Almost 1,000,000 Americans are found to have gallstones consistently, as indicated by the American Gastroenterological Association. Gallstones can shape when there’s an excess of cholesterol or waste in your bile, or on the other hand in the event that your gallbladder doesn’t void as expected.

At the point when gallstones block the conduits driving from your gallbladder to your digestion tracts, they can cause sharp agony in your upper-right mid-region. Prescription now and again breaks up gallstones, however, in the event that that doesn’t work, the subsequent stage is a medical procedure to eliminate the gallbladder.

Celiac Disease

Celiac illness is a serious aversion to gluten, which is a protein tracked down in wheat, rye, and grain. Eat gluten, and your safe framework goes on the assault: It harms your villi, the fingerlike distensions in your small digestion tracts that assist you with engrossing supplements from the food varieties you eat. In kids, side effects might incorporate stomach torment and swelling, runs, blockage, retching, and weight reduction. Side effects in grown-ups can likewise incorporate weakness, weariness, bone misfortune, wretchedness, and seizures.

Crohn’s Disease

Crohn’s sickness is important for a gathering of stomach related conditions called fiery inside illness. Crohn’s can influence any piece of the GI plot however most ordinarily influences the terminal ileum, which interfaces the finish of the little gut and the start of the colon. Several people might be impacted by Crohn’s, as per the Crohn’s disease.

Specialists don’t know what causes the sickness, yet it’s believed that hereditary qualities and family ancestry might have an impact. The most widely recognized Crohn’s side effects are stomach torment runs, rectal dying, weight reduction, and fever. “Treatment relies upon the side effects and can incorporate skin pain killers, immunosuppressants, and medical procedures.

Ulcerative Colitis

Ulcerative colitis is another incendiary inside sickness that might influence. The side effects of ulcerative colitis are basically the same as those of Crohn’s, however the piece of the gastrointestinal system impacted is exclusively the digestive organ, otherwise called the colon.

Assuming the resistant digestive system botches food or different materials for trespassers, bruises or ulcers foster in the colons covering. Assuming the experience successive and dire defecations, torment with the runs, blood in your stool, or stomach cramps, visit your PCP.

Medicine can stifle the irritation, and wiping out food sources that cause inconvenience might help also. In extreme cases, treatment for ulcerative colitis might include a medical procedure to eliminate the colon.


Little pockets called diverticula can shape anyplace there are points of concern in the covering of your stomach-related framework, however, they are most ordinarily tracked down in the colon. Assuming that you have diverticula yet no side effects, the condition is called diverticulosis, which is very normal among more seasoned grown-ups and seldom creates some issues. By age 50, about a portion of individuals has diverticulosis. However, in around 5% of individuals, the pockets become excited or contaminated, a condition called diverticulitis. Side effects incorporate fever, chills, sickness, and stomach torment. Heftiness is a significant gamble factor for diverticulitis.

Anal Fissure

Anal gaps are small, oval-formed tears in the coating of the finish of your gastrointestinal system called the anus. The side effects are like those of hemorrhoids, like draining and torment subsequent to moving your insides. Stressing and hard defecations can cause crevices, however so can delicate stools and looseness of the bowel.

Importance of Digestive System

Absorption is significant for separating the food into supplements, which the body utilizes for energy, development, and cell fix. Food and drink should be changed into more modest particles of supplements before the blood retains them and conveys them to cells all through the body. The body separates supplements from food and drinks into starches, protein, fats, and nutrients.


Carbs are the sugars, starches, and fiber tracked down in numerous food sources. Starches are called straightforward or complex, contingent upon their substance structure. Straightforward carbs incorporate sugars found normally in food varieties like natural products, vegetables, and endlessly milk items, as well as sugars added during food handling. Complex carbs are starches and fiber found in entire grain bread and oats, dull vegetables, and vegetables.


Food varieties like meat, eggs, and beans comprise huge atoms of protein that the body digests into more modest particles called amino acids. The body ingests amino acids through the small digestive system into the blood, which then conveys them all through the body.


Fat particles are a rich wellspring of energy for the body and assist the body with retaining nutrients. Oils, like corn, canola, olive, safflower, soybean, and sunflower, are instances of sound fats. Margarine, shortening, and nibble food sources are instances of less solid fats. During assimilation, the body separates fat atoms into unsaturated fats and glycerol.


Researchers characterize nutrients by the liquid in which they break up. Water-solvent nutrients incorporate all the B nutrients and L-ascorbic acid. Fat-solvent nutrients incorporate nutrients A, D, E, and K. Every nutrient plays an alternate part in the body’s development and wellbeing. The body stores fat-dissolvable nutrients in the liver and greasy tissues, while the body doesn’t effectively store water-solvent nutrients and flushes out the extra in the pee.

Conceptual Question

Question 1: Write about small intestine and large intestine?


  • Small intestine:-The muscles of the small digestive tract blend food in with stomach-related juices from the pancreas, liver, and digestive tract, and push the combination forward for additional processing. The walls of the small digestive tract assimilate water and the processed supplements into your circulatory system. As peristalsis proceeds, the byproducts of the stomach-related process move into the digestive organ.
  • Large intestine:-Byproducts from the stomach-related process incorporate undigested pieces of food, liquid, and more established cells from the coating of your GI lot. The digestive organ assimilates water and changes the loss of fluid in the stool. Peristalsis helps move the stool into your rectum.

Question 2: What happens to the digestive food?


The small digestive tract retains the majority of the supplements in your food, and your circulatory framework gives them to different pieces of your body to store or utilize. Exceptional cells assist assimilated supplements with crossing the digestive covering into your circulatory system. Your blood conveys basic sugars, amino acids, glycerol, and a few nutrients and salts to the liver. Your liver stores, cycles, and conveys supplements to the remainder of your body when required.

The lymph framework outer connection, an organization of vessels that convey white platelets and a liquid called lymph all through your body to battle contamination, retains unsaturated fats and nutrients. Your body utilizes sugars, amino acids, unsaturated fats, and glycerol to assemble substances you really want for energy, development, and cell fix.

Question 3: What is the function of the duodenum?


The duodenum is the principal fragment of the small digestive tract. It’s to a great extent liable for the nonstop separating process. The jejunum and ileum lower in the digestive system are primarily liable for the assimilation of supplements into the circulation system.

To assist with separating food, the small digestive tract gets stomach-related juices from different organs in your stomach-related framework, including your liver, gallbladder, and pancreas. Pipes from these organs feed into the duodenum. Chemical organs in the covering of the duodenum signal these organs to deliver their synthetic compounds when food is available.

Question 4: Write about the structure and function of the digestive system?


The intestinal system starts at the lips and finishes at the anus. It comprises the mouth, or oral hole, with its teeth, for crushing the food, and its tongue, which manipulates food and blends it in with spit; the throat, or pharynx; the throat; the stomach; the small digestive tract, comprising of the duodenum, the jejunum, and the ileum; and the internal organ, comprising of the cecum, a shut end sac interfacing with the ileum, the rising colon, the cross over colon, the plunging colon, and the sigmoid colon, which ends in the rectum. Organs contributing stomach-related juices incorporate the salivary organs, the gastric organs in the stomach covering, the pancreas, and the liver and its assistants — the gallbladder and bile conduits. These organs and organs add to the physical and synthetic separation of ingested food and to the possible disposal of nondigestible squanders. Their designs and works are portrayed bit by bit in this part.

My Personal Notes arrow_drop_up
Recommended Articles
Page :

Start Your Coding Journey Now!