Digestive System Overview and Functions

Digestive System Overview

• The digestive system is a collection of organs that breaks down food into energy.
• It involves the breakdown of food into small pieces and molecules.
• The digestive system is part of a larger system in the body known as the organ system.
• Other systems in the body include the nervous system, circulatory system and others.

Functions of the Digestive System

• Ingestion: Taking food into the mouth.
• Digestion: Breaking down food into smaller molecules that the body can use.
  • Mechanical Digestion: The physical breakdown of food. Examples include chewing, grinding, and moving food down the esophagus.
  • Chemical Digestion: The breakdown of food by using acids and enzymes.
• Absorption: Nutrients from food pass through the wall of the digestive system into your blood.
• Elimination: Substances that cannot be digested are eliminated from the body as feces. This is the removal of undigested matter in the body.

Digestive System Parts

• Alimentary canal: Tubular passage through which food passes
  • Mouth
  • Pharynx
  • Esophagus
  • Stomach
  • Small intestine
  • Large intestine
  • Rectum
  • Anus
• Accessory organs: Organs that help in the digestion process by secreting enzymes
  • Salivary glands
  • Liver
  • Gallbladder
  • Pancreas

Journey of Food: From Mouth to Anus

• Food begins its journey in the mouth where it is chewed.
• Salivary glands secrete saliva that moistens food.
• The chewed food, mixed with saliva called bolus, moves down the esophagus through peristalsis.
• The stomach digests food using digestive enzymes like hydrochloric acid and pepsin.
• The digested food, now called chyme, moves to the small intestine.
• The small intestine absorbs nutrients through folds called villi.
• Undigested food moves to the large intestine.
• Water is reabsorbed in the large intestine.
• The undigested matter (feces) is stored in the rectum and eliminated through the anus.

Common Digestive System Ailments

• Diarrhea: Characterized by loose, watery stools and frequent bowel movements. Often caused by bacteria or parasites.
• Constipation: Characterized by compact, dry, and hard stools. Can be caused by poor diet, low fiber intake, emotional stress, or other medical conditions.
• Gastroesophageal Reflux Disease (GERD): Acid from the stomach flows back into the esophagus. This happens when the muscular valve in the esophagus doesn't close properly.
• Gallstones: Hardened cholesterol and pigments in the bile build up in the gallbladder.
• Peptic Ulcer: A painful wound that occurs in the stomach, and sometimes the small intestine. It can be caused by bacteria that weakens the protective coating in the stomach lining.
• Colorectal Cancer: Tumors form in the lining of the large intestine.

Proper Care for the Digestive System

• Proper Nutrition: A balanced diet that supports all body functions.
• Proper Hygiene: Maintaining cleanliness to avoid contamination from foodborne illness
• Health Habits: Avoiding smoking and excess alcohol consumption.
• Regular Exercise: Helps digestion function better and maintaining healthy weight.