Full details about Human digestive systems and disorders of human digestive system

                  Human Digestive Systems

The human body is made of several organ systems that work together as one unit.
Digestive system
Disorders of digestive system

Digestive System:-

                                           Our body needs energy and food to move,grow and to stay alive.Our body cells cannot use the food in the form it is eaten by us.Our body changes it into simpler form.The process of changing the food into simpler form is called digestion.The parts of body that takes part in the process of digestion form the digestive system.

Where and how digestion occurs?                         

The process of digestion occurs in a long tube called alimentary canal.It starts from the mouth and ends at the anus. 

   Mouth:- 

The process of digestion starts from our mouth.Our teeth break the food into small pieces by cutting and grinding.The toungue mixes food with saliva which is secreted by salivary glands.Saliva starts the digestion of carbohydrates.After some time, the food in the mouth becomes soft and moist.The tongue pushes this food to the back of our mouth.

Oesophagus:-

The chewed food is then pushed from the mouth into the oesophagus.The oesophagus is a large tube that carries food from the mouth to the stomach.
          The oesophagus use wave like muscular movements to push the food to the stomach.These wave like movements are called peristaltic movements and process is called peristalsis.

Stomach:- 
                   Our stomach is a larged  j-shaped muscular bag. It mixes the food with digestive juice.The digestive juice begins the digestion of proteins.The food spends about four hours in the stomach.The digestive juice in the stomach also contain an acid.The acid kills the germs present in our food.It also helps in the digestion of proteins.

    Small Intestine:-

                               As food leaves our stomach,it is passed on to the small intestine which is a long,thin tube coiled inside our abdomen.Final digestion of carbohydrates,fats and proteins occurs in the small intestine.Three organs helps in the digestion of food here.These are the liver,pancreas and wall of the small intestine.The pancreas and intestinal wall of the small intestine.The liver provides bile salts to make fats easier to absorb.The pancreas and intestinal walls secrete juices to digest the remaining food.The absorption of the digested food also occurs in the last part of the small intestine.The inner surface of small intestine has many finger-like structures called villi.The digested food passes into the blood through the walls of the villi.The blood carries food particles to all parts of the body. 

Large Intestine:-

                                The undigested part of the food passes into the large intestine.Here the undigested food has a large amount of water.The main job of large intestine is to absorb extra water.The undigested food becomes solid and is called faeces.The faeces is stored in the last part of the large intestine called the rectum,We pass the faeces out  of our body through the anus.

Disorders of Digestive System

Some common digestive system disorders are diarrhoea,heartburn,constipation,ulcer,gas-trouble,etc.

Diarrhoea:-

       Diarrhoea is passing semi-liquids feaces.it may be caused by an infection,eating contaminated food,a reaction to some medicine or just anxiety or excitement.

           Some of the common symptoms of diarrhoea are : abdominal pain,cramping,bloating,nausea,loose motions,fever and bloody stools.

Preventions:-

1.Always wash your hands with soap after using the toilet.

2.Wash all fruits and vegetables before cooking or eating.

3.Don't eat uncooked meat and eggs.

Constipation:- 

Constipation is adifficult or painful passing of feaces.During the period of constipation some persons may passes feaces three or less than three times a week.It is a common digestive disorder in Pakistan.

      Constipation is caused by taking food low in fibre,lack of physical ativity,not drinking enough water,delay in going to the washroom,etc.We can avoid constipation by:

1.Adopting a proper lifestyle

2.Taking regular exercise 

3.Eating lots of fibre fruits

4.Drinking plenty of water

5.Going to the washroom when we have the urge