Biology: B1

• Plant cell structures


  • Cell wall
  • Cell membrane
  • Vacuole
  • Nucleus
  • Mitochondria
  • Chloroplast
  • Ribosomes
• Animal cell structures


  • Cell membrane
  • Cytoplasm
  • Nucleus
  • Ribosomes
  • Mitochondria
• Cell wall


  • Holds shape of the cell/Supports
• Cell membrane


  • Controls what goes in and out
• Vacuole


  • Contains cell sap
• Nucleus


  • Controls the cell, contains DNA
• Mitochondria


  • Where respiration happens
• Chloroplast


  • Where photosynthesis happens
• Ribosomes


  • Where proteins are made
• Cytoplasm


  • Where chemical reactions happen
• Bacteria cells have a simple cell structure, are prokaryotic, and contain a cell wall, cell membrane, ribosomes, chromosomal DNA and plasmid DNA
• OSMOSIS in potatoes


  1. Cut potato in equal sizes

  2. Weigh and blot

  3. Put in different concentrations of sucrose solutions

  4. Take out, blot and weigh

  5. Calculate percentage change in weight
• Enzymes can be affected by temperature and pH
• Optimum temperature


  Temperature where enzyme works fastest
• Denaturation


  Breaking up of protein, causing it to lose its shape
• Food tests


  1. Starch: Add iodine, blue-black colour

  2. Reducing sugars: Add Benedict's solution, heat, green/orange/red colour

  3. Proteins: Add copper sulfate, purple colour

  4. Fats: Add ethanol, shake, cloudy
• Carbohydrate digestion


  Broken down by amylase into sugars (glucose for respiration)
• Protein digestion


  Broken down into amino acids (to make enzymes)
• Lipid digestion


  Broken down by lipases into fatty acids and glycerol (for respiration)
• Diffusion


  1. No energy needed, substances transported: CO2, O2, water, food substances

  2. From high to low concentration across partially permeable membrane
• Osmosis


  1. No energy needed, substance transported: water

  2. From high to low water concentration across partially permeable membrane
• Active transport


  Energy from respiration needed, substances transported: minerals, ions into blood
• Using a microscope


  1. Place slide on stage

  2. Use lowest power objective lens

  3. Adjust light source

  4. Turn focus wheel until clear
• Enzyme


  Biological catalyst that breaks things down, active site must match substrate