The human digestive system

• Why is digestion important?

  It breaks down large and insoluble food into small molecules.
• What happens to food in the mouth?

  Food is mechanically broken down and mixed with saliva.
• What does the salivary gland produce?

  Saliva and the enzyme amylase.
• What is the function of the oesophagus?

  It transports food to the stomach.
• What occurs in the stomach during digestion?

  The stomach churns food and mixes it with hydrochloric acid.
• What enzymes does the stomach produce?

  Protease enzymes.
• What is the role of the small intestine in digestion?

  It continues to digest food and absorbs small soluble molecules.
• What adaptations does the small intestine have for absorption?

  • Very large surface area due to villi and microvilli
  • Good blood supply with many capillaries supplying the villi
• What is the function of the large intestine?

  It absorbs water and forms waste for excretion.
• What does the rectum do?

  It stores waste before excretion.
• What enzymes does the pancreas produce?

  Amylase, protease, and lipase.
• What is the role of the liver in digestion?

  The liver produces bile, which aids in digestion.
• What does the gall bladder do?

  It stores bile and releases it into the small intestine.
• How is bile released into the small intestine?

  It is released from the gall bladder.