Digestive System Sudarshana Elapatha
National Dip. In Teaching
The digestive system serves for digestion of
complex food into
simpler end products which are capable of being absorbed.
Digestion
Process of
food gets shaped into
bolusby the action of
The
in
converts
starch sugar.in to
amylase enzyme
is capable of Antibacterial
Action
by the a virus which infects
the salivary
mumps is caused
glands
The disease
the oesophagus
through the pharynx.
The food bolus in the buccal cavity,
enters
The pharynx is common to both respiratory tract and alimentary canal.
.
The oesophagusFood that enters
Cardiac sphincter
down toThe
The oesophagus
with the aid of
peristaltic contractions
Stomach
with an inner lining of longitudinal folds.
is a thick
Muscular sac Muscular sac
is formed when food in the stomach is ground for 3-4 hours.
StomachA semifluid paste called
Stomach wall
&HCl acid Pepsin Renin
secretes
on the
food
coagulate milk
Stomach
Renin
serves to
of children
in the
pepsin
Polypeptide
is formed as a result of
incomplete digestion of proteins
by
pepsinProte
ins Polypeptide
In theStomach
GastritisBurning sensation in
the stomach
Gastritis Burning sensation in the
stomach
condition can initiate from intake of
food
highly acidicoily or spicy
not taking meals
timeat proper&
anxiety
Gastritis Burning sensation
in the stomach smokingcertain drugs alcoholintake of contribute to
gastritis condition
Small intestine consists of
3parts namely
Duodenum
Jejunum
Ileum
Duodenum Pancreatic juice
And Bile is secreted
on to the food which enters the
secreted from the
Food is made
basicby the
BILE
liver
The pancreatic juice contains
3Enzymes
Amylase
Lipase Trypsin
Amylase
and similar enzymes
Formation of
fromGlucose
Carbohydrate by the action of
Lipase
Fats Fatty acids &are formed by the action of
onLipids
Trypsin
proteins.
are formed by the action of
on
Amino acids
Food is digested
further by the addition of
intestinal juices in the
jejunum
are simple products of food .
Glycerol Fatty acids
Amino acids Glucose
of simple end products of food
take place mainly
in the small intestine.
Absorption
The ileum is modified
to absorb the digested
final food products.
finger like structures
called
The inner wall of the ileum bears
Villi
Villi provide
more surface area
to nutrients
to be absorbed.
The Villi encapsulate a network of
blood capillaries anda lymphaticvein
(lacteal).
Glucose and Amino acids
absorb into blood capillaries
fatty acids and glycerol
absorb into
lacteals
It is long in structure,Hence the chyme remains inside it for a longer period of timeVilli provide more surface area to nutrients to be absorbed.
Villi encapsulate a network of bloodcapillaries and a lymphatic vein.
Substances which are not absorbed
passes to the
large intestine.
All the required nutrients
except water are absorbed to the body
by the timethey pass to the large intestine.
water Is reabsorbedBy the large intestine.