Organisation - Biology Paper 1

• Cell


  Building block of life
• Tissue


  Group of similar cells
• Organ


  Group of different tissues that carry out a specific function
• Organ system


  Group of organs that make up an organism
• Organism


  Group of organ systems that together make up a living being
• Mitosis is needed for growth and repair
• Mitosis is asexual reproduction because it requires one parent cell
• Mitosis

  • Single parent cell with 46 chromosomes
  • Chromosomes duplicate - 92 chromosomes
  • Cell divides to form 2 genetically identical daughter cells which both have 46 chromosomes
• Each enzyme has a specific active site
• When the temperature is too high or the pH isn't right, the enzyme will denature
• One substrate can fit into the active site like a key fits a lock. Once it is attached, the substrate is changed into a product
• Amylase

  • Breaks down carbohydrates into sugars
  • Produced in salivary glands, pancreas, and small intestine
• Protease

  • Breaks down proteins into amino acids
  • Produced in the stomach, pancreas, and small intestine
• Lipase

  • Breaks down fats into fatty acids
  • Produced in the pancreas and small intestine
• Bile is made in the liver and stored in the gall bladder
• The effect of pH on amylase

  1. Put a test tube containing starch solution and a test tube containing amylase in a water bath at 37°C

  2. After 5 minutes, add the amylase solution to the starch

  3. Every 30 seconds, take a drop from the mixture and test it for starch using iodine solution

  4. Record how long it takes for the starch to be completely digested