Transcript digestive

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Components of the digestive system
The alimentary canal
Digestive glands
Human digestive system
The digestive system of a rat
Peristalsis
The structure and functions of a
villus
The digestive system in mammals
Alimentary
canal
Digestive
glands
a tube from
mouth to anus
they produce
enzymes for
digestion
The alimentary canal
oesophagus
stomach
large intestine
small intestine
rectum
anus
Digestive glands
• salivary glands
saliva
• gastric gland
gastric juice
• liver
bile
• pancreas
pancreatic juice
• intestinal gland
intestinal juice
Human digestive system
Digestive system of a rat
stomach
small intestine
liver
large intestine
Peristalsis
The rhythmic contraction and relaxation of
• muscle
behind
the
muscles
of thethe
gut wall to move food
food
bolus
along
the
alimentary canal
contracts
• muscle in front of
the food bolus
relaxes
 food bolus is pushed along the gut
Structure and function of a villus
lacteal
villus
with
blood
transports
one
cell
thick
increase
capillaries
fats
andarea
surface
and
a lacteal
glucose
for absorption
muscle
wall
Summary
The digestive system
• is the system of organs that are involved
in the process of digestion
• is made up of the alimentary canal and
associated glands
Movement of food along the alimentary canal
• by peristalsis
Absorption of digested food
• by villi