The digestive system notes

Digestive System

, INTRODUCTION
• Digestion is defined as the process by which food is broken down into simple chemical
substances
that can be absorbed and used as nutrients by the body. Most of the substances in the diet
cannot be utilized as such.


These substances must be broken into smaller particles.
• Then only these substances can be absorbed into blood
and distributed to various parts of the body for utilization.


• The digestive system is responsible for these functions.

, FUNCTIONAL ANATOMY OF THE
DIGESTIVE SYSTEM
Digestive system is made up of
• Gastrointestinal tract (GI tract) or alimentary canal and
• Accessory organs, which help in the process of digestion and absorption
• GI tract : is a tubular structure extending from the mouth up to anus with a length of about 30 feet.
• It opens to the external environment on both ends.
GI tract is formed by two types of organs:
1. Primary digestive organs
2. Accessory digestive organs.

, 1. Primary Digestive Organs

• Primary digestive organs are the organs where actual digestion takes place.
• These organs are:
1. Mouth
2. Pharynx
3. Esophagus
4. Stomach
5. Small intestine
6. Large intestine.