More on Enzymes and digestion

• Enzymes used in the digestive system are produced by specalised cells in glands and in the gut lining.
• Different enzymes catalyse the breakdown of different mood molecules.
• What do salivary glands produce?

  Amylase enzyme
• What is the role of the tongue in digestion?


  The tongue helps in the manipulation of food
• What are the three main functions of the stomach?

  It pummels food, produces pepsin, and secretes hydrochloric acid
• What enzyme does the stomach produce?

  Pepsin
• Why does the stomach produce hydrochloric acid?


  To kill bacteria and provide the right pH for pepsin
• What is the pH level of the stomach's environment?


  pH 2 – acidic
• What is the function of the large intestine?


  To absorb excess water from food
• What enzymes does the pancreas produce?


  Protease, amylase, and lipase
• What happens in the small intestine?


  It produces enzymes and absorbs digested food into the blood
• What is stored in the rectum before excretion?


  Faeces made up mainly of indigestible food
• What is digestion?

  The process of turning large insoluble molecules into small soluble ones which can be absorbed into the bloodstream.
• What enzyme do the salivary glands produce?

  Amylase
• What enzyme does the stomach produce?

  Protease, Pepsin
• What enzymes doesd the pancreas produce?


  protease, amylase and lipase.
• Where do the enzymes from the pancreas go to?


  The small intestine
• Exam question:

  Name three parts of the digestve system that produce protease enzymes. [3 marks]


  Stomach [1 mark], pancreas [1 mark], and small intestine [1 mark]
• What is the primary function of the digestive system?

  To break down food into tiny pieces for absorption
• What are the three main groups of nutrients that humans need?

  Carbohydrates, proteins, and fats
• Why is digestion necessary for humans?

  It breaks down large molecules in food for absorption
• What is the role of saliva in digestion?

  It helps make the food mixture more liquid and contains salivary amylase
• What enzyme is found in saliva that aids in digestion?

  Salivary amylase
• What happens to food after it is swallowed?

  It passes down the esophagus to the stomach
• What is the stomach primarily described as?

  A muscular sac
• What are the three important functions of the stomach?

  Mixing food, producing pepsin, and producing hydrochloric acid
• What type of enzyme is pepsin?

  A protease enzyme
• What is the role of hydrochloric acid in the stomach?

  It kills bacteria and provides an ideal environment for pepsin
• What happens to food after it leaves the stomach?

  It is squeezed into the small intestine
• What is the primary function of the small intestine?

  To absorb digested food into the bloodstream
• Which organ produces most of the digestive enzymes?

  The pancreas
• What does the gallbladder release into the small intestine?

  Bile
• What are the two main roles of bile?

  Neutralizing stomach acid and emulsifying fats
• Where is bile produced?

  The liver
• How does bile help in fat digestion?

  By emulsifying fats into tiny droplets
• How is the lining of the small intestine adapted for absorption?

  It has villi that increase surface area and a good blood supply
• What are villi?

  Finger-like projections in the small intestine
• Why is a good blood supply important for the villi?

  It maintains the concentration gradient for nutrient absorption
• What happens to undigested material in the small intestine?

  It passes into the large intestine
• What is the function of the large intestine?

  To absorb excess water and leave behind feces