The Process Of
Food Digestion - A Fascinating
Story
Second one comes from pancreas and third
one from small intestines. Juice from small intestine trickles from many places along the way. Small intestine is
quite long about 5 to 6 times longer than your own height. It is properly folded in the abdomen. Most of the
digestion takes place in this small intestine.
The digestion process is somewhat complicated. Pancreatic juices contain many enzymes
and hormones. These help breaking down of peptones ( derived from proteins ) into individual amino
acids.
Pancreatic juice also digests both fats
and carbohydrates. Carbohydrates get converted into soluble glucose by pancreatic juice. Similarly, Lactose (
present in milk ) is also converted into soluble glucose.
Fats are digested to give simpler substances with the help of another kind of
secretion of liver.
The liver is the chemistry
laboratory of the human body.
Blood flows from heart to liver. The liver controls the level of sugar in the blood
& storage of such sugars in the muscles. It takes amino acids from the blood and makes them into proteins and
stores it.
It releases these proteins when required by the body. It also destroys poisonous
substances and stores vitamins and minerals.
All the food which is by now broken down into simple, mostly water soluble
substances is absorbed in the body through small intestine.
The inner lining of the small intestine has a number of tiny, finger like
projections called villi. These are sucking organs which seize the digested materials and transfer them to the
blood. Blood carries these nutrients through circulatory process
to various organs of the body.
Some part of digested fats also gets carried away through another network
called lymphatic system. This system also empties its contents in
blood, somewhere near the neck.
Vitamins and minerals are often water soluble and are not broken down further
& absorbed in the blood after being detached from the food when other nutrients get digested. Vitamin A which
is fat-soluble, gets absorbed in the small intestine somewhat like fat itself.
Food which we eat finally reaches blood. It is then carried
to all parts of the body, to supply their needs of energy and the body building and regulation of body
functions.
Large intestine
process:
The large
intestine is situated next to small intestine and is tubular in shape. Its inside is smooth without any
projections. It is placed in abdomen in the shape of English letter U upside down.
As the digested food passes along the intestine, water is absorbed from through the
walls and into the blood. The food becomes less liquid and becomes hard. Breaking down of the digested food gives
rise to some substances which carry bad smell. The undigested food is then thrown out of the body in the form of
stools through the opening called Anus.
How the digested food is made
useful?
Carbohydrates (starches & sugars) are
broken down first in mouth and then in the small intestine into simple sugars chiefly glucose.
Glucose is absorbed by the villi of the
small intestine directly into the blood stream. It travels all over your body and is used by muscles as a source of
energy for their working.
A small part of glucose is converted into glycogen which is the form in which glucose
is stored both in muscles (about two thirds) and in the liver (about one third).
Some glucose is always circulating in the blood and the level is steady. When the
sugar level goes up it is a sign of a fault -- such as the disease diabetes.
Fats are broken by way of intermediate simpler forms eventually into glycerol
& fatty acids. Part of these fatty acids directly go into the blood and then to the liver as does glycerol.
These fatty acids are either used for energy or sent via blood to other parts of body. They then may be used for
energy or built back into fats, which are despatched through the blood for storage as fatty tissues.
Any excess food which we eat above our requirements is
converted into and stored away mostly in the form of fat. When we get insufficient food (e.g. during fasting) fat
deposits are first used up.
Proteins reach blood stream as amino
acids which are their building blocks. At various places in the body, these amino acids are picked up by the body
organs and built into variety of compounds.
Tissue proteins, enzymes, hormones and so many other chemical compounds are
protein in nature. Liver itself makes and stores body proteins.
Vitamins and minerals are also stored in the liver. Whenever body needs them,
these are released to the body parts and organs.
Conclusion
There are thousands of interconnected processes going on in our body, all the
time. Food is digested and then absorbed in the small intestine. All the absorbed vital nutrients are then
circulated via blood to different body parts / organs. And the process goes on.
By: Pradeep Mahajan
(Source : Your food & You -- By K.T.Achaya )
Last updated : Aug 5, 2010
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