Page 199 - Physiology and Pathophysiology MNU 2024-2025 نظرى

Clinical pharmacy 2024/2025 Level 2 Pharm D Physiology and Pathophysiology (MD303)
Digestive system

1) Functions

Primary function:

Transfer nutrients, water & electrolytes from ingested food  into body’s internal
environment

Main Four functions

1. Motility
2. Secretion
3. Digestion

4. Absorption
1- Motility
For movement of food through the GI tract.

a. Ingestion Taking food into the mouth.
Chewing the food and mixing it with saliva.
b. Mastication

c. Deglutition Swallowing the food.
Rhythmic wave-like contractions that move food through GIT.
d. Peristalsis

e. Segmentation Two-way movement of chyme in small intestine for mixing of

contraction food.
2- Secretion

Exocrine Endocrine

Secreted into the lumen of the GIT. Stomach and small intestine secrete
hormones into blood to help regulate the
GI system

As digestive enzymes, mucus, electrolytes, As Gastrin, secretin & CCK
and water (cholecystokinin)

3- Digestion

Biochemical breakdown of structurally complex foodstuffs into smaller, absorbable units

4- Absorption

Small units resulting from digestion, along with water, vitamins, and electrolytes are
transferred from digestive tract lumen into blood or lymph “for fat."

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