Digestive System - Function, Definition, Organs | Eduauraa

The digestive organs are the Gastrointestinal (GI) Tract or digestive tract, liver, gallbladder, and pancreas.

The Gastrointestinal tract is a chain of empty organs joined with one another like a hollow, twisting tube from the mouth to anus.

The series of organs include the mouth, esophagus, stomach, small and large intestine.

The other important organs of the digestive system are the Liver, Pancreas, and Gallbladder.

The small intestine has three parts- duodenum, jejunum, and ileum. The large intestine has the appendix, cecum, colon, and rectum. 

The bacteria, also known as microbiome or flora in our GI tract, helps process digestive functions.

Our circulatory or nervous system also helps the digestive system partially.

All these organs with hormones and blood work together to digest the solid and liquid food we consume daily. 

Importance of Digestive System

The digestion system helps the body consume nutrients from food and drink to run the body properly and keep us healthy.

The nutrients include proteins, carbohydrates, fat, vitamins, minerals, and water.

The digestive system breaks the nutrients into small units for complete absorption to generate energy, ensure growth and wellbeing. 

a. Carbohydrates break into Glucose. 

b. Fats break into fatty acids.

c. Protein-enriched food items break into amino acids.

How does the Digestive System work?

Every ‘digestive system’ organ enables the movement of solid and liquid food items through the gastrointestinal tract.

The food and liquids break into smaller elements. Our body can absorb the nutrients and meet the requirement as needed in different body parts.

The large intestine absorbs water, and the by-product of digestion comes out as stool.

The nervous system and hormonal functions control the digestive process. 

Functions of the Organs of the Digestive System-

a. Mouth: Chewing

b. Esophagus: Peristalsis 

c. Stomach: Upper Muscle and Lower Muscle helps the stomach to let in the food by moving the organ wall, and the lower muscle helps the food to mix with the digestive juice and enzyme 

d. Small Intestine: Peristalsis 

e. Large Intestine: Peristalsis

How does the food move through the Gastrointestinal Tract?

The consumed food items move through the gastrointestinal tract through the peristalsis process.

The twisting empty organs of the GI tract comprise a muscle layer that allows the organ walls to move.

The movement enables the solid and liquid food to enter the GI tract and mixes the elements with every organ.

The muscles behind squeeze and contracts the food, and the muscles in the front, relax the stomach to move the food. 

1. Mouth

When the food is swallowed, our tongue pushes the food towards the throat.

Epiglottis, a small tissue, folds the windpipe to save us from choking, and the food smoothly passes into the following organ series. 

2. Esophagus

After the food gets swallowed, the digestive process becomes automatic.

The muscles receive signals from the brain, and peristalsis begins.

3. Lower Sphincter

As the food reaches the end of the Esophagus, the lower sphincter, a ring-like muscle, relaxes the stomach and lets the food in.

After the food passes into the stomach, the sphincter closes itself to prevent the backflow of the food upwards.

4. Stomach

The stomach muscles mix the food with the digestive juices after the food enters the stomach.

The stomach slowly passes the chyme to the intestines.

5. Small Intestine

The small intestine muscles help the food particles mix with the digestive juices emitted from the pancreas, liver, and intestine.

Then, the small intestine pushes the food further.

The intestine walls absorb the water and nutrients from the food and mix it with the bloodstream. 

6. Large Intestine

The waste left after the digestion process includes the indigested parts of the food and older cells. The large intestine absorbs the water and turns the liquid waste into the stool. The muscle movement helps the stool to reach the rectum.

7. Rectum

Rectum stores the stool and pushes it out of your anus during any bowel movement. 

How does the Digestive System break Food?

When the food moves through the GI tract, the digestive organ breaks the food into smaller particles by chewing, squeezing, and mixing the particles with digestive juices, bile, acid, and enzymes. 

The mouth starts the digestive process by chewing.

The saliva moistens the food, and it moves through the long muscle to the stomach.

The enzymes of the saliva break the food into starches.

After we swallow the food, Peristalsis pushes the food to the stomach.

Stomach glands break down the food further with stomach acid and enzymes, and the stomach muscles mix the food with digestive juices.

Digestive juice from the Pancreas breaks the food into carbohydrates, protein, and fat.

The pancreas sends the digestive juice through tubes to the small intestine.

Then, bile or the liver digestive juice digests the fat and vitamins.

Then, ducts or tubes carry bile to the gallbladder.

Gallbladder stores bile and squeezes the bile through the bile tube to the small intestine.

The bacteria in the Small Intestine create enzymes to digest carbohydrates.

Bacteria in the Large Intestine break the remaining nutrients and creates vitamin K. 

What happens to the Digested Food?

The small intestine absorbs the necessary nutrients and, the circulatory system passes the nutrients to different parts of the body as required.

Particular cells help the absorbed nutrients to mix into the bloodstream.

The blood carries amino acids, sugar, glycerol, salt, and vitamins to the liver.

The liver processes, stores and sends the nutrients to the different parts of the body. 

The lymph system carries white blood cells and a fluid called Lymph in the body to prevent any kind of infection.

What controls the Digestive System?

Hormones and nerves work together to control the digestive system.

The central nervous system and the enteric nervous system send signals during the digestive process and control the functions by speeding up or delaying the process.

Similarly, the hormones send a signal to the brain to initiate digestion on time. 

This article has provided us a detailed discussion on the human digestive system. Hope the information helps you with your studies!