Digestive System Functions and Processes

Digestive System Function and Structure

• The digestive system is a group of organs that work together to break down food into nutrients the body can use.
• Ingestion – food enters the mouth.
• Mechanical digestion – chewing, churning, and mixing food to break it down. (e.g., mastication in mouth, churning in stomach)
• Chemical digestion – using enzymes to break down food into smaller molecules. (e.g., saliva's amylase)
• Digestion - breaking down food mechanically and chemically to release nutrients
• Absorption - nutrients are absorbed into the bloodstream
• Excretion - waste products are eliminated from the body.

Digestive Processes

• Ingestion: Food enters the mouth.
• Deglutition: Food moves from the mouth to the esophagus.
• Mechanical Digestion: Includes mastication (chewing) and churning in the stomach.
• Chemical Digestion: Enzymes break down food (e.g., amylase in saliva, pepsin in stomach)

Types of Digestion

• Mechanical digestion:
  • Chewing (mastication): Breaking food into smaller pieces.
  • Churning (mixing): Mixing food with digestive juices.
• Chemical digestion:
  • Enzymes: Proteins that speed up chemical reactions in the body.
  • Specific enzymes break down different nutrients: carbohydrates, proteins, and fats.

Absorption

• Absorption: Nutrients are taken from the digestive tract into the bloodstream.
• This occurs mainly in the small intestine.
• The walls of the small intestine have a large surface area to maximize absorption.

Excretion

• Excretion: Waste products are eliminated from the body.
• This occurs mainly through the large intestine and anus.

Explore the intricate functions and structure of the digestive system in this quiz. Learn about the stages of digestion, including ingestion, mechanical and chemical digestion, absorption, and excretion. Test your knowledge of how these processes work together to convert food into essential nutrients.