Anatomy and Physiology of Digestive System

Syahruramdhani, MSN, M.Sc

School of NursingMedical Faculty and Health Sciences

Universitas Muhammadiyah Yogyakarta

Objectives

• Name and locate the organs

• Describe the general appearence of the organs

• Describe the function of the organs

Digestive System

• The digestive system is the organ system

that processes food, extracts nutrients

from it, and eliminates the residue.

• The digestive system has two anatomical

subdivisions, the digestive tract and the

accessory organs.

Digestive System

• The digest ive tract also known as the

alimentary canal. It includes the mouth,

pharynx, esophagus, stomach, small intestine,

and large intestine.

• The accessory organs are the teeth, tongue,

sal ivary g lands, l iver, gal lb ladder, and

pancreas.

Digestive System

1. Ingestion

2. Secretion

3. Mixing and propulsion (Motility)

4. Digestion (Mechanical and Chemical)

5. Absorption and

6. Defecation

Mouth (Teeth and Tongue)

• The mouth, also referred to as the oral or

buccal cavity.

• The cheeks and lips play important roles in

procuring food and keeping it in the mouth.

• The palate is a wall or septum that separates

the oral cavity from the nasal cavity, and

forms the roof of the mouth.

Mouth (Teeth and Tongue)

• The teeth are collectively called the dentition.

• They serve to masticatethe food, breaking it

into smaller pieces.

• This not only makes the food easier to swallow,

but also exposes more surface area to the

action of digestive enzymes and thus speeds

up chemical digestion.

Mouth (Teeth and Tongue)

• The tongue although muscular and bulky, is an

agile and sensitive organ with several functions:

• it aids in food intake;

• it has sensory receptors for taste, texture, and

temperature that are important in the acceptance

or rejection of food;

• it compresses and breaks up food; it maneuvers

food between the teeth for mastication;

Mouth (Teeth and Tongue)

• it secretes mucus and enzymes;

• it compresses the chewed food into a soft

mass, or bolus ,that is easier to swallow;

• it initiates swallowing; and

• it is necessary for articulate speech.

Salivary Gland

• Saliva moistens the mouth, digests a small

amount of starch and fat, cleanses the

teeth, inhibits bacterial growth, and

moistens food and binds particles together

to aid in swallowing.

• It is a solution of 97.0% to 99.5% water

Salivary Gland

• salivary amylase,an enzyme that begins starch digestion in the mouth;

• lingual lipase,an enzyme that is activated by stomach acid and digests fat after the food is swallowed;

• mucus, which binds and lubricates the food mass and aids in Swallowing;

Salivary Gland

• lysozyme, an enzyme that kills bacteria;

• immunoglobulin A (IgA),an antibody that inhibits bacterial growth; and

• electrolytes, including sodium, potassium, chloride, phosphate, and bicarbonate salts.

Salivary Gland

• There are two kinds of salivary glands, intrinsic and extrinsic.

• The intrinsic salivary include lingual glands in the tongue, labial glands on the inside of the lips, and buccal glands on the inside of the cheeks.

• The extrinsic salivary include parotid, sublingual and submandibula glands.

Salivary Gland

Pharynx and Esophagus

Stomach

• Stomach is organ with “J” shaped that connect esophagus and small intestine.

• Base on anatomy, histology and function divide into 3 parts, they are:

1. Fundus

2. Body

3. Antrum

Stomach

References

• Tortora, G. J., & Derrickson, B. H. (2008). Principles of anatomy and physiology. John Wiley & Sons.

• Guyton AC, Hall JE (2006). Textbook of Medical Physiology, 11th ed. Chapter 5, Pages: 307-326.

• Saladin K (2003). Anatomy and Physiology: The Unity of Form and Function, 3rd ed. Chapter 23,

Pages: 879-913.

• Scanlon VC, Sanders T (2007). Essential of Anatomy and Physiology, 5th. Chapter: 18, Pages: 417-

438.