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
• 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 definition of a tissue?

  A group of cells with similar structure
• 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
• What are the three main nutrients found in food?

  Carbohydrates, proteins, and lipids
• Why must large food molecules be digested?

  They are too large to be absorbed directly
• How are large food molecules broken down?

  By enzymes during digestion
• What happens to small molecules after digestion?

  They are absorbed into the bloodstream
• What is the role of saliva in digestion?

  It contains enzymes that digest starch
• What does hydrochloric acid do in the stomach?

  It helps enzymes digest proteins
• What is the function of the stomach muscles?

  They churn food to increase surface area
• What does the pancreas release into the small intestine?

  Enzymes that digest starch, protein, and lipids
• What is the role of bile in digestion?

  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 is released from the body at the end of digestion?

  Feces
• What are the products of digestion used for in the body?

  To build new carbohydrates, lipids, and proteins
• What is glucose used for in the body?

  It is used in respiration
• What nutrients are found in food?

  • Carbohydrates (starch)
  • Proteins
  • Lipids (fats)
• 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, lipids, and absorbs nutrients
  • Large intestine: Absorbs water and forms feces
• What is the role of enzymes in digestion?

  • Break down large food molecules into smaller ones
  • Facilitate absorption of nutrients into the bloodstream
• What is the process of digestion in the digestive system?

  1. Large food molecules are broken down by enzymes.
  2. Small molecules are absorbed into the bloodstream.
  3. Products of digestion are used to build new molecules.