Digestion

• where is lipase produced?


  in the pancreas
• where is amylase produced?

  Pancreas and salivary glands.
• where is maltase produced?

  Small intestine lining
• where is protease produced?

  Protease is produced in various organs and tissues, including the stomach lining, pancreas, and small intestine.
• where is amylase secreted into?

  Mouth
• where is maltase secreted into?

  Small intestine
• where is protease secreted into?

  stomach
• where is lipase secreted into?

  Small intestine
• what does amylase act on and produce?

  acts on starch to produce maltose
• what does maltase act on and produce?

  acts on maltose and produces glucose
• what does protease act on and produce?

  acts on protein and produces amino acids
• what does lipase act on and produce?


  acts on lipids to produce fatty acids and glycerol
• what is the function of the mouth?


  Ingestion, chewing, and initiating digestion (mechanical).
• what is the function of the salivary glands?


  Produces a liquid that lubricates food and also contains amylase which breaks down starch into glucose 
• what is the function of the oesophagus?


  to be a tube which passes food to the stomach
• what is the function of the stomach?


  Churns food, mechanical digestion. Hydrochloric acid kills any microbes taken in with the food.  Creates correct pH for protease. Protease breaks down protein into amino acids- chemical digestion.
• what is the function of the pancreas?


  Produces the enzymes amylase, protease and lipase to be added to food as it leaves the stomach
• what is the function of the liver?


  Produces bile, a green alkaline substance that increases the surface area of fats.  It also neutralises the acid from the stomach
• what is the function of the gall bladder?

  Stores bile.  It will be added to the food as it leaves the stomach
• What is the function of the small intestine?

  It's where the enzymes amylase, protease, lipase and maltase are added to the food to digest it using chemical digestion. Absorption of soluble molecules across the wall and into the wall.
• What is the function of the Large intestine?

  Mostly fibre and water is found here. Water is absorbed into the bloodstream, fibre is compacted.
• What is the function of the appendix?


  The appendix has no useful function in humans
• What is the function of the rectum?


  The rectum functions as the final section of the digestive system where feces are stored before elimination. Fibre an undigested solid waste is stored here.
• What is the function of the anus?


  The anus functions as the opening through which solid waste is eliminated from the body.
• What is Peristalsis?


  Peristalsis is when the circular muscles behind the mass contract forcing the mass along the tube and the muscles surrounding the mass relax allowing for the tube to stretch and pass along.
• A food contains starch. Describe in as much detail as you can what happens to this starch after the food is ingested. (4)

  As soon as the starch is ingested it is mechanically digested by the teeth and the salivary glands release a liquid which lubricates the starch and contains an enzyme, amylase, which breaks the starch down into maltose. It then passes down the the oesophagus into the stomach. In the small intestines, the walls produce another enzyme called maltase, the maltase breaks down the maltose into glucose, for it to then be absorbed by the blood for use in respiration.
• A food contains protein. Describe in as much detail as you can what happens to this protein after the food is ingested (4)

  • mechanically digested by teeth and/ or stomach
  • Digested/ made soluble by protease enzyme in stomach
  • Digested/ made soluble by protease enzyme in the small intestine
  • Protease made in the pancreas
  • Into amino acids
  • amino acids/ small molecules absorbed into blood
• What happens to lipids in food after ingestion

  1. Mechanical digestion by teeth and stomach to become smaller molecules

  2. Bile made in liver and stored, released into small intestine to emulsify lipids into smaller droplets

  3. Increased surface area for lipase enzyme to act

  4. Lipase enzyme produced in pancreas, works in small intestine to chemically digest lipids into fatty acids and glycerol, which are absorbed into blood
• Experiment to investigate the importance of bile method


  1. Label boiling tubes A, B and C

  2. Transfer 5cm cubed of milk and 2 cm cubed of Sodium Carbonate into each tube

  3. Add one drop of phenolphthalein to each tube

  4. Add 1cm cubed of distilled water to tubes A and C

  5. Add 1cm cubed of Bile Salts to tubes B and C

  6. Add 1cm cubed of Lipase to tubes A and B

  7. Start stopwatch

  8. Watch tubes and note time when pink colour disappears

  9. Record results in a table
• Label the diagram

  A) Epithelial cell

  B) microvilli

  C) venule

  D) lacteal

  E) mucosa tissue layer

  F) sub mucosa tissue layer

  G) lymphatic vessel

  H) goblet cells

  I) arteriole

  J) blood capillary

  K) epithelium

  
• What does isomerase act on and produce?


  isomerase acts on glucose to produce fructose