The Human Digestive System and How It Works

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The Human Digestive System and How It Works
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The Food Starts in the mouth. It is the mouths
job to increase the surface area of the food by
manually chewing it. This is also where the
saliva first meets the food to moisten it.
THE MOUTH
The tongue is one of the important devices in
the mouth. It is a muscle that moves food within
the mouth. It sub-consciously pushes food into
the proper places for it to be chewed and
swallowed properly.
The teeth are the other important devices of the
mouth. They grind, cut, tear, and rip food into
many pieces with strong force and therefore
creating more surface area for the enzymes to
come into contact with.
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The mouth contd. In the mouth, two kinds of
digestion take place

• Mechanical Digestion
• The teeth crush, grind, tear, and cut food into
  little pieces that make the stomach be able to
  eat away and break it down a lot easier.

• Chemical Digestion
• The saliva has an enzyme which breaks down the
  food far enough so it can easily travel down the
  esophagus.

Salivary Glands These are glands in the upper
rear section of the jaw that produce a liquid
called saliva. This saliva contains enzymes, a
sort of biological catalyst. These glands send
this liquid to the mouth where they begin to
break down the food.
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The Epiglottis
The epiglottis is a flap of tissue that closes
the opening to the trachea (air pipe) during
swallowing to prevent food from going the wrong
direction. (food or drink going into the lungs)
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• The esophagus
• the esophagus is a tube that connects the mouth
  to the stomach. Food is squeezed through this
  tube and to the stomach by peristalsis. This is
  contractions of the muscles that line the
  esophagus.

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Sphincters 1 2 The sphincter is a tight muscle
that opens to allow food to enter the stomach
and closes to prevent food from traveling back
up the Esophagus. This also prevents the ailment
called heartburn. The second sphincter Is at the
bottom of the stomach, preventing food from
leaving the stomach prematurely
Stomach The stomach is a storage and digestion
facility situated in the central torso region. It
providestwo functions digestion and storage. In
the digestion function, the stomach uses acids
and enzymes to break down the food. In the
storage function, it simply puts the food into
layaway until the rest of the digestive system
is ready for it.
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The Liver and Bile

• The Liver quite simply a production plant.
• It is designed to produce bile.
• This bile is what gives our feces its all too
  famous colour.
• This bile is then sent off to the Gall Bladder
  where it is stored until needed.

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Bile
Bile

• Bile is a material produced in the liver that is
  designed to be able to mix fat and water.
• It is stored in the Gall Bladder until needed.
• If a person has their gall bladder removed, the
  liver drips the bile directly into the small
  intestine.

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The gall bladder

• The gall bladder is simply a storage facility. It
  stores bile until the small intestine is ready
  for it.
• It takes all Bile from the liver and acts as the
  middle man, giving it to the small intestine.

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pancreas

• Produces and squirts out chemicals into the small
  intestine
• These chemicals release enzymes to help breakdown
  food.
• These Chemicals also neutralize the acidity of
  the stomach acids on their way through.

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SMALL INTESTINE

• Is highly folded with villi (small hills in the
  sides of the tube). This helps to increase the
  surface area of the tube so that the blood stream
  can absorb nutrients much easier.

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Appendix

• The appendix is a small, little finger shaped
  object that many people claim has no function in
  todays human. Despite what these people say,
  several scientists have studied it and say that
  it carries semi-crucial bacteria that is part of
  the every day immune system.

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LARGE INTESTINE
The large intestine is a very crucial part of the
digestive track. It helps absorb water from the
digested material which prevents liquid fecal
matter (diarrhea). This is also the spot where
E-Coli bacteria are released into the digested
material to help break it down. The longer food
spends in this intestine, the more water will be
absorbed from it.
RECTUM
The rectums primary function is to hold fecal
matter until this material is ready to be
evacuated by defecation (disposed of into the
sewers)
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Anus
The anus is the final sphincter in the human
body. It prevents feces from coming out
prematurely, and keeps it in the Rectum.
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DIGESTIVE DISORDER
Cholesterol stones are made up of Hardened
cholesterol, and are usually yellowish green.
80 of all gallstones Fall into this
category. Pigment stones are small dark
stones made of Bilirubin.
GALLSTONES

• What are they? Gallstones are hardened Bile in
  the Gall bladder. If the liquid bile contains too
  much cholesterol, bile salts, or bilirubin, under
  certain conditions it can harden into stones.

There are 2 types of gallstones, Cholesterol
stones and pigment stones
Gallstones can be as small as a grain of sand
or as large as a golf ball.
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Gallstones Contd

• CAUSES
• Bile Hardens in the Gall Bladder, Blocking the
  common bile duct.
• It is also believed that the presence of a
  gallstone may cause more to form, like a growing
  bacteria in a way.
• SYMPTOMS
• Steady pain in upper abdomen
• Pain between shoulder blades
• Nausea/vomiting
• Abdominal bloating
• Recurring intolerance of fatty foods
• Belching
• Gas / indigestion
• Chills
• Low- grade fever
• Yellowish colour of the skin / whites of eyes
• Clay-coloured stools

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Gallstones Contd

• Treatment
• Surgery is the most common method. They simply
  remove the Gall Bladder. Called Laparoscopic
  surgery.
• Non surgical
• Oral Dissolution Therapy
• Drugs made from bile acid are used to dissolve
  the stones
• Contact dissolution Therapy
• In experimental stages
• Pharmaceutical drugs injected directly into the
  gall bladder

DONT PEOPLE NEED THEIR GALLBLADDER????? Fortunate
ly the gallbladder is an organ that people can
live without. Losing it wont even require a
change in diet. Once the gallbladder is removed
the bile flows out of the liver through the
hepatic ducts instead of the common bile duct
and goes directly into the small intestine
without the storage facility in between.
However, because the bile isnt stored in the
gallbladder, it flows into the small intestine
more frequently causing diarrhea in about 1 of
people who have this surgery.
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GALLSTONESKEY POINTS TO REMEMBER

• Gallstones form when substances (cholesterol or
  pigment) in the bile harden.
• Symptoms can be the same as many other problems
  such as heart attacks, so an accurate diagnosis
  is crucial.
• Laparoscopic surgery is the most common way to
  remove the gall bladder and gallstone problem.

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