Ecology Required Practicals

Field Investigations Practicals

Preparing microscope slide with onion skin
Investigation 1. Population size
  1. Using two tape measures, create a 20m x 20m square in a field.
  2. Use a random number generator to obtain two random numbers between 0 and 20. Use the numbers as coordinatesa long the tape measures.
  3. Set down a quadrat at the coordinates.
  4. Count and record the number of Daisies inside the quadrat.
  5. Repeat steps 2 - 4 nine more times to have a total of ten measurements.
  6. Add up the number of Daisies recorded inside all ten quadrats.
  7. Estimate the total number of Daisies in the 20x20m field using the equation:
    Total population size=Total AreaArea sampled×Number of Daisies recorded in sampled areas
Setting up the microscope with prepared slide
Investigation 2. Effect of variation in a factor
  1. Lay a tape measure from the base of a tree to an open area of ground.
  2. Place a quadrat touching the 0m mark on the tape measure.
  3. Count and record the number of daisies in the quadrat.
  4. Repeat step 3, placing a quadrat at 5m intervals along the tape measure until the end of the transect line.
  5. Plot a graph of the number of daisies against the distance from the 0m mark.



Decay Practical

Preparing petri dish
1
Preparing Test Tubes
  1. Add 5cm3 of Lipase solution into a test tube and label as "Lipase".
  2. Add 5 drops of Cresol Red indicator into a different test tube and label as "Milk".
  3. Add 5cm3 Milk into the "Milk" tube.
  4. Add 7cm3 Sodium Carbonate solution to the "Milk" tube, which should result in a purple solution.
Setting up the microscope with prepared slide
2
Doing Science
  1. Place a thermometer in the "Milk" tube.
  2. Place both tubes in a beaker of water at 20°C.
  3. Wait for the "Milk" tube to reach the same temperature as the water.
  4. Transfer 1cm3 of Lipase from the "Lipase" tube into the "Milk" tube and start a timer immediately.
  5. Record the time taken for the solution in the "Milk" tube to turn yellow.
  6. Repeat all above steps at the same water temperature twice more and calculate a mean.
  7. Repeat all above steps at a different water temperture, increasing in incriments of 10°C until 60°C.