Digestive System is a group of organs
that convert food into energy to supply the entire body and eliminates waste
material.
The Digestive system begins at the mouth /oral
cavity, pharynx, esophagus, stomach, small intestines, large intestines, rectum,
and ends at the anus.
There are few accessory organs that assist in
digestion (Teeth, tongue, salivary glands, liver, gallbladder, and pancreas).
Anatomy
of Digestive System
The GI Tract (Gastrointestinal Tract) starts
from the mouth, inside the mouth, there are many accessory organs that assist in
the digestion of food are,
1. The tongue,
2. The teeth,
3. Salivary glands (Parotid, Sub-lingual and Sub-mandibular glands)
Teeth chop food into small pieces, then it is moistened by saliva then tongue pushes the food into the pharynx.
The pharynx is a funnel-shaped tube connected to the posterior end of the mouth. It moves the chewed food from the mouth to the esophagus.
The pharynx also plays a role in the respiratory system, as air from the nasal cavity, passes through the pharynx on it's way to the larynx and to the lungs. The pharynx contains a flap of tissue known as the epiglottis that acts as a switch to route food to the esophagus and air to the larynx.
The esophagus is a muscular tube connecting the pharynx to the stomach. cardiac sphincter is present in the junction between esophagus and stomach.
1. The tongue,
2. The teeth,
3. Salivary glands (Parotid, Sub-lingual and Sub-mandibular glands)
Teeth chop food into small pieces, then it is moistened by saliva then tongue pushes the food into the pharynx.
The pharynx is a funnel-shaped tube connected to the posterior end of the mouth. It moves the chewed food from the mouth to the esophagus.
The pharynx also plays a role in the respiratory system, as air from the nasal cavity, passes through the pharynx on it's way to the larynx and to the lungs. The pharynx contains a flap of tissue known as the epiglottis that acts as a switch to route food to the esophagus and air to the larynx.
The esophagus is a muscular tube connecting the pharynx to the stomach. cardiac sphincter is present in the junction between esophagus and stomach.
The stomach is a muscular sac that is located
on the left side of the abdominal cavity, just inferior to the diaphragm. It
acts as a storage place for food so that it digests large meals properly.
The
stomach contains HCL (hydrochloric acid) and digestive enzymes that aids in breaking
down the large substance into smaller substances. Then the digested material
passes to the Small intestine via pyloric sphincter.
The small intestine is located just inferior to
the stomach and takes up most of the space in the abdominal cavity. The entire
small intestine is coiled like a hose and the inside surface is full of many
ridges and folds. These folds are used to maximize the digestion of food and
absorption of nutrients.
By the time food leaves the small intestine, around 90%
of all nutrients have been extracted from the food.
The small intestine is divided into,
1. Duodenum
2. Jejunum
3. Ileum
Accessory digestive organs found in the abdominal
region are,
1. Liver
2. Gallbladder
3. Pancreas
The liver is an accessory organ of the digestive system located to the right upper quadrant of the abdomen, the right side of the stomach, just inferior to the diaphragm and superior to the small intestine.
The liver is the largest internal organ in the body. The liver has many different functions in the body, but the main function of the liver in digestion is the production of bile and its secretion into the small intestine (duodenum).
2. Gallbladder
3. Pancreas
The liver is an accessory organ of the digestive system located to the right upper quadrant of the abdomen, the right side of the stomach, just inferior to the diaphragm and superior to the small intestine.
The liver is the largest internal organ in the body. The liver has many different functions in the body, but the main function of the liver in digestion is the production of bile and its secretion into the small intestine (duodenum).
The gallbladder is a small, pear-shaped organ
located just inferior to the liver. The gallbladder is used to store and
recycle excess bile from the small intestine so that it can be reused for the
digestion of subsequent meals.
The pancreas is a large gland located just
inferior and posterior to the stomach. The pancreas secretes digestive enzymes
into the small intestine to complete the chemical digestion of foods. The endocrine function of the pancreas is Insulin production.
From Small intestine, the digested food passes to the large intestine. via Ileocecal valve.
From Small intestine, the digested food passes to the large intestine. via Ileocecal valve.
The large intestine is a long, thick tube divided
into,
1. Cecum,
2. Ascending colon,
3. Transverse colon,
4. Descending colon,
5. Sigmoid colon
6. Rectum
7. Anus
The large intestine is located just inferior to the stomach and wraps around the superior and lateral border of the small intestine. The large intestine absorbs water and contains many symbiotic bacteria that aid in the breaking down of wastes to extract some small amounts of nutrients. Faeces in the large intestine exit the body through the anal canal.
2. Ascending colon,
3. Transverse colon,
4. Descending colon,
5. Sigmoid colon
6. Rectum
7. Anus
The large intestine is located just inferior to the stomach and wraps around the superior and lateral border of the small intestine. The large intestine absorbs water and contains many symbiotic bacteria that aid in the breaking down of wastes to extract some small amounts of nutrients. Faeces in the large intestine exit the body through the anal canal.
Functions
of the digestive system:
- Ingestion
- Secretion
- Mixing and
movement
- Digestion
- Absorption
- Excretion
Common disease of
Digestive system:
1.
GERD – Stomach acid flows
backwards causing discomfort
2.
Crohn’s disease - Inflammation
that affects the lining of the digestive tract.
3.
Irritable bowel syndrome- Is a problem that affects the large intestine.
4.
Diverticulosis - Small,
bulging pouches develop in the digestive tract.
5.
Colitis - Inflammation of the inner lining of the colon.
6.
Colon Polyp - A small clump of cells
that forms on the lining of the colon.
Common Signs and Symptoms of
Digestive system
1. Abdominal pain
2. Blood in the stool
3. Bloating
4. Constipation
5. Diarrhea
6. Heartburn
7. Incontinence
8. Nausea and vomiting
MEDICAL TERMS:
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1. Mouth - Oral / Stomato
2. Lip - Labio / Cheilo
3. Tooth - Dento / Odonto
4. Tongue - Glosso / Linguo
5. Uvula - Uvulo
6. Salivary gland - Sialo
7. Gums - Gingivo
8. Pharynx - Pharyngo
9. Esophagus - Esophago
10. Stomach - Gastro
11. Duodenum - Duodeno
12. Jejunum - Jejuno
13. Ilium - Ilio
14. Liver - Hepato
15. Gallbladder - Cholecysto
16. Common bile duct - Choledocho
17. Bile - Chol
18. Small Intestine - Entero
19. Colon - Colo
20. Cecum - Ceco
21. Sigmoid colon - Sigmoido
22. Rectum - Procto / Recto
23. Anus - Ano
MEDICAL ABBREVIATIONS:
1. CT - Computed tomography
2. ERCP - Endoscopic retrograde cholangiopancreatography
3. GERD - Gastroesophageal reflux disease
4. GI – Gastrointestinal
5. HCL - Hydrochloric acid
6. IBS - Irritable bowel syndrome
7. IBD - Inflammatory bowel disease
8. LFT - Liver function test
9. LLQ - Left lower quadrant
10. LUQ - Left upper quadrant
11. MRA - Magnetic resonance angiography
12. MRI - Magnetic resonance imaging
13. RLQ - Right lower quadrant
14. RUQ - Right upper quadrant
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