How digestive system works?

Digestion is the breaking down of food mechanically and chemically with the help of enzymes into smaller particles.In the digestion process,the food is broken down and the nutrients in the food are absorbed and used by our body.

The digestive system is made up of the alimentary canal (also called the digestive tract)and other abdominal organs that runs from the mouth to the anus.

Our body uses food as a fuel to provide energy for work and also for our growth.

When you eat, when you smell a tasty food, see it, or think about it,enzymes released into your mouth and starts the process of digestion.

Enzymes helps to breakdown the food quickly and easily.

Mouth

Your teeth breaks the food  into small pieces to makes it easy to swallow.Amylase enzymes breakdown the starch into sugars in the mouth and small intestine.The saliva(contains amylase) produced by the salivary glands lubricates and break down the food quickly.The tongue helps to swallow the chewed-up food called bolus by pushing it down to the back of your throat(or pharynx).

Don't Gulp down your food!


Properly chew your food and then swallow it.

If you gulp and don't chew properly,your food may get stuck in your esophagus (otherwise called gullet) and blocks your lung airways and causes choking hazards.   


Don't eat fast in a hurry and be the victim of digestive problems.Eating fast makes you to eat a lot and can make you obese.

Do you know why you start coughing while you eat sometimes?

Windpipe allows air to come in and out of the body is also located at the back of your throat.


When you swallow  food or liquids, a special flap called the epiglottis flops down over the opening of your windpipe to make sure the food enters the esophagus and not the windpipe.

When you drink too fast, the epiglottis won't have enough time to flop down,so the food enters the windpipe in a wrong way and you start coughing involuntarily to clear your windpipe.

The swallowed food  passes through the following organs:


  1. Esophagus or gullet
  2. Stomach
  3. Small intestine
  4. Liver
  5. Large intestine
  6. Anus

1.Esophagus or gullet
 From the throat,food enters the pipe(10 inches) called esophagus.

esophagus/gullet = Food pipe/ food tube

The strong muscles surrounding the esophagus using wave-like muscle movement(peristalsis)  pushes the food down to the stomach in two to three seconds.Even when we are upside-down,we are able to eat or drink only because of this muscle movement.

2. Stomach

Stomach is a sack-like and "J" shaped organ which stores the food received from the esophagus.Your stomach is located just below the heart.

Protease enzymes breakdown the proteins into amino acids in the stomach and small intestine.Digestion of proteins in the stomach is helped by hydrochloric acid.

The walls of the stomach contain strong muscles and gastric juices.The strong muscles of the stomach churns and grind up the food into tiny particles. In addition to breaking down food,the gastric juice(mainly hydrochloric acid) produced in the stomach,also helps to kill many harmful microorganisms that might have been swallowed along with the food.

Your stomach moves along with gastric juice and breaks down the food into a thick liquid paste called chyme.

3.Small Intestine

From the stomach, food(chyme) enters the duodenum, the first part of the small intestine.Followed by the jejunum and then enters the ileum (the final part of the small intestine).

The small intestine break down the food and helps in the absorption of nutrients with the help of pancreas, liver and gall bladder.

Lipase enzymes breakdown the fats and oils into fatty acids and glycerol in the small intestine.Digestion of fat in the small intestine is helped by bile, made in the liver.

95% of absorption of nutrients occurs in the small intestine.

* The pancreas makes the enzymes that digest proteins, carbohydrates and fats and sends it  to the small intestine through a tube called the pancreatic duct.

* The liver secretes bile.

*The gall bladder injects bile in the small intestine(duodenum) to digest the fat in the food.Bile secreted by the liver is stored in the gall bladder until when it is needed by the body for digestion.

 When the chyme is fully digested,it becomes a very thin, watery mixture and the  nutrients( vitamins, minerals, proteins, carbohydrates and fats )in it are absorbed by millions of tiny finger-like objects called villi and are sent into your bloodstream where the nutrients can travel to all your body cells.

4.Liver

Before going to the rest of the body, the nutrient-rich blood comes to the liver for processing.The liver is body's central processing system and the largest solid organ in the body.It converts harmful substances to less toxic forms and regulates the amount of blood in the body.Liver cleans your blood and stores energy sources like fat and sugar as reserve,but sends proteins out into the bloodstream to supply the rest of the body.

Waste stuff in the blood which  your body doesn't need  are carried by bile back into the intestine and are sent out of the body as stool.During processing,some waste goes through your blood to your kidneys and will be out as pee.


5.Large Intestine

From the small intestine,the watery mixture which can't be used by the body(ie.,undigested food mainly fibre) comes to the large intestine.

The appendix is an organ connected to the cecum.(not does anything in digestive system)

The Large intestine consist of three parts - cecum,colon and rectum

* The first part of the large intestine is called the cecum with very fluid contents.

* After that when the watery mixture passes through the colon in the large intestine,water and minerals are absorbed and it become solid.This solid food waste called poo is pushed to the rectum.

* Rectum - stores the poo until you have a bowel motion.If the poo stays here for more than 3 days,it will be dried.This is called as getting constipated.
When you have a bowel movement,the muscles around the rectum pushes the poo out through the anus.


6.Anus

Anus is the exit point of the digestive tract where poo leaves your body.


 digestive system