The Digestive System
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The Digestive System
Consists of the alimentary canal ‫القناة الهضمية‬and
several accessory organs ‫عدد من األعضاء المساعدة‬.
‫الفم‬mouth
Pharynx
‫البلعوم‬
Esophagus
‫المرئ‬
Parts of the
Alimentary Canal
Stomach
‫المعدة‬
small intestine
‫االمعاء الدقيقة‬
large intestine
‫االمعاء الغليظة‬
anal canal ‫القناة الشرجية‬
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The
Alimentary
Canal
The Alimentary Canal
•A tube ‫ أنبوبة‬that extends ‫ تمتد‬from the mouth to the anus
•Consists of four layers ‫ طبقات‬4:
-outer layer (protects) ‫الطبقة الخارجية للحماية‬
-second layer (muscular ‫ ;العضلية‬contracts ‫ تنقبض‬and expands
in wavelike motions called peristalsis ‫)حركة تموجيه لدفع الغذاء‬
-third layer (vessels ‫اوعية‬, nerves and glands that nourish
‫ تغذي‬and carry away waste ‫)تطرد الفضالت‬.
-innermost layer ‫( الطبقة الداخلية‬mucous membrane ‫ غشاء مخاطي‬that
secretes mucus ‫ المخاط‬and digestive enzymes) ‫االنزيمات الهاضمة‬
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Tongue
Mouth
Tooth
Parotid
salivary
gland
Pharynx
Organs of the Digestive System
Organs of the
Digestive System
Sublingual
salivary gland
Submandibular
salivary gland
Liver
‫الكبد‬
Gall bladder
Duodenum
Esophagus
Stomach
Pancreas
Large intestine
Small
intestine
Anal canal
Rectum
‫المستقيم‬
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food
mouth
Tracing Toast
pharynx
epiglottis
esophagus
stomach
anus
feces
rectum
Tracing food through the
alimentary canal
sigmoid
colon
duodenum
jejunum
ileum
descending
colon
transverse
colon
ascending
colon
cecum
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Mouth
lips
Mouth
The lips ‫ الشفاه‬protect the mouth
from receiving food that is too
hot or too rough on the surface.
•The mouth is also called the oral cavity
•Food is taken into the mouth and chewed ‫يمضغ‬
with the assistance of the cheek muscles ‫عضالت‬
‫الوجه‬
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The Tongue
•Process of chewing is
called mastication ‫المضغ‬
•The tongue moves the food
around to prepare it for
deglutition (swallowing) ‫البلع‬
..
. ..
.
Tongue
‫اللسان‬
•Small raised areas called papillae are located
on the tongue and they contain taste buds ‫براعم‬
‫التذوق‬
•The frenulum connects the tongue to the floor
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of the mouth.
Mouth
• Functions
– mechanical digestion
• teeth
– break up food
– chemical digestion (saliva ‫)اللعاب‬
• amylase enzyme
– digests starch
• mucus
– protects soft lining of digestive system
– lubricates food for easier swallowing
• buffers
– neutralizes acid to prevent tooth decay
• anti-bacterial chemicals
– kill bacteria that enter mouth with food
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Salivary Glands
Salivary Glands
‫الغدد اللعابية‬
•parotid
Tongue
Tooth
•submandibular
•sublingual
Parotid gland
Submandibular gland
Sublingual
gland
The function of the salivary glands is to make saliva and help the
bolus (soft mass of chewed food) go down the esophagus easily.
Saliva contains enzymes which help break down food to a form
which
the
body
can
use.
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Pharynx
Pharynx
•Muscular tube about 5 inches long in adults
•Also known as the throat
•Transmits food into the esophagus
•The epiglottis (a flap of tissue) covers the
trachea ‫ القصبة الهوائية‬to prevent food from entering
the larynx ‫ الحنجرة‬during swallowing which causes
choking ‫ االختناق‬.
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Esophagus
Esophagus
•Muscular tube about 9 to10 inches long in
the
adult
that
contracts
rhythmically
(peristalsis) to propel ‫ تدفع‬food toward the
stomach
•Contains a group of muscles called the lower
esophageal sphincter that closes off the
entrance to the stomach to prevent reflux ‫عودة‬
of food, emesis or regurgitation (vomiting).
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