The Digestive System

• What is meant by a tissue?

  A group of cells with similar structure
• What is an organ?

  A group of tissues working together
• What is an organ system?

  A group of organs working together
• What are the main organs in the digestive system?

  Mouth, esophagus, stomach, small intestine, large intestine
• What is the function of muscle cells?

  They can contract to facilitate movement
• Why do muscle cells contain many mitochondria?

  To provide energy needed for contraction
• What is the role of glandular tissue in the stomach?

  It releases enzymes for digestion
• What is the function of the digestive system?

  To break down food and absorb nutrients
• Why must large food molecules be digested?

  They are too large to be absorbed into the bloodstream
• How are large food molecules broken down?

  By enzymes during digestion
• What happens to food in the mouth?

  It is chewed and mixed with saliva
• What role do enzymes in saliva play?

  They begin to digest starch into sugars
• What is the function of hydrochloric acid in the stomach?

  It helps enzymes digest proteins
• What happens to food in the stomach?

  It is churned into a fluid for digestion
• What chemicals are released into the small intestine?

  Enzymes from the pancreas and bile from the liver
• What does bile do in the digestive process?

  It speeds up lipid digestion and neutralizes acid
• How are small food molecules absorbed in the small intestine?

  By diffusion or active transport
• What happens in the large intestine?

  Water is absorbed into the bloodstream
• What are the products of digestion used for in the body?

  To build new carbohydrates, lipids, and proteins
• What are the main functions of the digestive system organs?

  • Mouth: Chews food and begins starch digestion
  • Esophagus: Transports food to the stomach
  • Stomach: Digests proteins and churns food
  • Small intestine: Digests proteins, starch, and lipids; absorbs nutrients
  • Large intestine: Absorbs water and releases feces
• What is the process of digestion in the digestive system?

  1. Ingestion of food
  2. Digestion of large molecules into small molecules
  3. Absorption of small molecules into the bloodstream
  4. Utilization of nutrients by the body
  5. Excretion of waste products
• What is the role of enzymes in digestion?

  • Break down large food molecules into smaller ones
  • Facilitate absorption of nutrients into the bloodstream