| Basic
Information The digestive
system contain organs for
changing food chemically for
absorption by body tissues. It is
also responsible for processing
food , breaking it down into
usable protein, minerals,
carbohydrates and fats and other
substance. The digestion process
involves breaking food into
simple soluble substances
absorbable by tissues.
The digestion process includes
both mechanical and chemical
processes. The mechanical
processes include chewing to
reduce food to small particles,
the churning action of the
stomach, and intestinal
peristaltic action. The three
chemical reactions take place :
conversions of carbohydrates into
such simple sugars as glucose,
breaking down of protein into
such amino acids as alanine, and
conversion of fats into fatty
acids and glycerol. These
processes are accomplishes by
specific enzymes.
The Digestive Journey
The digestive process starts
in your mouth when you start
eating. The salivary glands
produce secretions that are mixed
with the food. The saliva breaks
down starches into dextrin and
maltose. Then it goes down your
esophagus in peristaltic waves to
the stomach. This only takes the
matter of seconds. The stomach
contains gastric juice and the
gastric juice contains chemicals
such as hydrochloric acid and
some enzymes, including pepsin,
rennin, and lipase.
Pepsin breaks proteins into
peptones and proteoses. Rennin
separates milk into liquid and
solid portions and lipase acts on
fat. Another function of stomach
digestion is gradually to release
materials into the upper small
intestine, where digestion is
completed.
After the solid food has been
digested the fluid remaining is
called chyme When it is
thoroughly digested it pass
through the pylorus sphincter to
the small intestine. Here in the
small intestine all the nutrients
are absorbed from the chyme into
the bloodstream leaving the rest
or the unusable residue. The
residue pass through the colon or
large intestine to the rectum.
The solid waste, called feces
pass through the canal and
the anus.
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