The Digestive System

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• The digestive system is a group of organs working together to convert complex food substance in to simple ones to facilitate absorption in to the blood stream.•Consists of

- gastrointestinal tract - accessory organs of digestion (tongue, salivary glands, pancreas, liver, and gallbladder) 2

• Six major functions take place in the digestive system:

- Ingestion

- Secretion

- Mixing and movement

- Digestion

- Absorption

- Excretion

Functions of Digestive System

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Essential organs and their function

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Digestion

•A process of altering complex foodstuff and converting them into simple constituents in order to be absorbed in the blood.

• Two processes of digestion:

•Mechanical

•Chemical

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Mechanical process Mastication Swallowing Peristalsis

Chemical ProcessThe chemical process consists of all the changes brought about by the enzymes of the digestive juices

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Gastric Juice The fluid that is secreted by various glands in the mucous membrane of the stomach. It generally contains …. Hydrochloric Acid Water Mucus Pepsinogen Mineral salts Intrinsic Factors

Fig. Oxyntic gland

Oxyntic/parietal cellCanaliculi

Mucous neck cell

Oxyntic GlandOxyntic means Acid forming

Secretes –

HCl, Pepsinogen, mucus, intrinsic factors

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Role of hydrochloric acid

1. gives acid reaction required by the gastric enzymes

2. kills bacteria

3. controls the pylorus and starts peristalsis

4. stops the action of ptyalin

5. converts pepsinogen to active pepsin

(Pepsinogen HCl Pepsin)

Diseases of the upper part

• GERD• GERD induced acid erosion of

the teeth and halitosis.• Esophagitis• Gastritis• Peptic ulcer

Diseases of the lower part

• Enteritis• Diarrhea• Appendicitis• Ulcerative colitis• Irritable bowel syndrome• Hemorrhoids

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Adnan-Ul-islam B.Pharm.(Hon’s) adnan.ru.bd@gmail.com