Required practicals

• Microscopy


  1. Prepare thin layer of onion skin

  2. Place on slide and add iodine stain

  3. Place cover slip

  4. Start with lowest magnification lens

  5. Use coarse and fine focus to find specimen

  6. Increase magnification if needed

  7. Measure cell size using graticule
• Osmosis


  1. Cut equal-sized cylinders from vegetable

  2. Place in test tubes with different sugar solution concentrations

  3. After time, remove, dab dry, and reweigh

  4. Calculate percentage change in mass

  5. Plot against solution concentration to find concentration with no osmosis
• Enzymes


  1. Measure set volume of enzyme and substrate solutions

  2. Mix and start timer

  3. Every 10 seconds, test for presence of substrate using iodine

  4. Record time for complete reaction

  5. Repeat with different temperatures or pH values

  6. Plot time against temperature/pH and identify optimum
• Food tests


  1. Grind solid food and make solution

  2. Test for starch using iodine

  3. Test for glucose/simple sugars using Benedict's solution

  4. Test for proteins using biuret reagent

  5. Test for lipids by adding ethanol then water
• Photosynthesis


  1. Set up pond weed in inverted test tube/cylinder

  2. Measure distance from light source

  3. Count bubbles or measure oxygen volume in set time

  4. Repeat at different distances

  5. Plot against distance and identify relationship
• Microbiology


  1. Spot bacterial cultures on agar plate

  2. Observe growth over time

  3. Or spread culture to make lawn and add antibiotic discs

  4. Measure clear zones around discs

  5. Use aseptic techniques throughout
• Decay


  1. Measure milk/cream volume

  2. Add sodium carbonate and phenolphthalein indicator

  3. Add lipase enzyme

  4. Measure time for solution to decolorize at different temperatures

  5. Plot time against temperature to find optimum