Biology paper 1 Organisation

• What are multicellular organisms made up of?

  organ systems
• What are similar cells made up?

  tissues
• What is a tissue?

  a tissue is a group of similar cells that work together to carry out a function?
• What's an example of a tissue?

  epithelial tissue

  • made up of epithelial cells
  • it covers some parts of the human body ( inside of the gut )
• What are organs made up of?

  tissues
• What is an organ?

  an organ is a group of different tissues that work together to perform a certain function.
• What's an example of organ?

  stomach is a organ

  • epithelial tissue lines the inside and outside of the stomach
• What are organ systems made up of?

  organs
• What is an organ system?


  an organ system is a group of organs working together to perform a function.
• What's an example of an organ system?

  digestive system

  • it breaks down and absorbs food
• What does the digestive system include?

  large intestine, liver, salivary glands, stomach, pancreas, small intestine
• What does the liver do?

  produce bile
• What does the salivary glands do?

  produce digestive juices
• What does the small intestine?

  digest food and absorbs soluble food molecules ( glucose )
• What does the large intestine do?

  absorbs water from undigested food leaving poo ( faeces )
• What does the pancreas do?

  produces digestive juices
• What is a catalyst?


  A catalyst is a substance which increases the speed of a reaction, without being changed or used up in the reaction
• What are enzymes?


  living things have tons of reactions going on inside their cells that are controlled by enzymes

  enzymes are large proteins

  they speed up reaction inside living things by acting as catalysts
• What does every enzyme has?

  active site with a unique shape
• What theory do enzymes have?

  key and lock theory
• How do enzymes work?

  the substance involved in the reaction has to fit into the active site for the enzymes to work so enzymes are really picky - they usually only catalyse one specific reaction
• What do enzymes need?

  right temperature, right pH
• What's the optimum temperature?

  temperature that they work best at
• How does the temperature affect the enzymes?

  if it gets too hot, some of then bonds holding the enzyme together break

  this changes the shape of the enzymes of the enzymes active site, so the substrate won't fit any more - the enzyme is denatured
• How does the pH affect the enzymes?

  if the pH is too high or too low, it affects the bonds holding the enzymes together. this changes the shape of the active site and denatures the enzyme
• What is optimum pH?

  pH they work best
• What's the method too the effect of pH on enzyme activity?

  • put a drop of iodine solution into a every well of a spotting tile
  • set up a water bath at 35'
  • add some amylase solution and buffer solution with a pH of 5 to a boiling tube
  • add starch to the boiling tube, mix and start a stop clock
  • every 30 secs, take sample from the boiling tube using a dropping pipette, drop on the spotting tile
  • the iodine solution stays brown- orange all the starch in the sample has been broken down.
  • repeat the experiment
• What is starch?


  carbohydrate
• What are big molecules?

  fats. proteins, starch
• Why are starch, proteins and fats big molecules?

  too big to pass through the walls of the digestive system so digestive system breaks these big molecules down into smaller ones, the smaller ones can then be absorbed into the bloodstream
• Where does amylase work?

  mouth and small intestine
• Where do proteases work?

  stomach and small intestine
• What do proteses turn into?

  amino acids
• Where are lipases?


  pancreas and small intestine
• Where do lipases work?

  small intestine
• What do lipases turn into?

  glycerol and fatty acids
• Where is bile stored?

  gall bladder before released into the small intestine
• What solution do you use to test for sugar?

  benedicts
• What colour does a high concentration of sugar turn ( food test)

  brick red
• What colour does a meduim concentration of sugar turn ( food test)

  yellow