1. Compare the electron and light microscope
Triangle to calculate Magnification
Required Practical 1 – Microscopy
Use a light microscope to observe, draw and label a selection of plant and animal cells.
Converting units
1cm = mm
1mm = μm
1 μm = nm
Define magnification
Define resolution
Label the picture below
Complete the table
Size of image mm
Magnification
Actual size μm 5
X 200 15 25
X 400 10
Write a method for this practical
Compare the electron and light microscope
Explain the importance of using a mounted needle, cover slip and stain

2. What is meant by the zone of inhibition? How do you calculate it?
Variables
Independent:
Dependent:
Control:
Required Practical 2 – Microbiology (GCSE Biology only)
Investigate the effect of antiseptics or antibiotics on bacterial growth using agar plates and measuring zones of inhibition.
What is meant by the zone of inhibition? How do you calculate it?
How did you work aseptically?
Why do you not seal the lid of the petri dish?
Method
Calculate the zone of inhibition for each antiseptic
Why are the petri dishes stored upside down at 25◦C?
Describe the difference between antibiotics, antiseptics and disinfectants.
How could you improve the
Precision:
Accuracy:
State and explain which antiseptic was the most effective.

3. Required Practical 3 – Osmosis Analysis and Conclusion
Variables
Independent:
Dependent:
Control:
Required Practical 3 – Osmosis
Investigate the effect of a range of concentrations of salt or sugar solutions on the mass of plant tissue.
Expected Graph
Definition of Osmosis
Method
Results
1.0 M sugar solution
0.5 M sugar solution
Distilled water
Initial mass (g)
10 
 10
Final mass in (g)  5
 25
% Change in mass in
How could you improve the
Precision:
Accuracy:
Analysis and Conclusion
Define the terms
Hypotonic:
Hypertonic:
Isotonic:

4. Describe what is happening in the graph Variables Independent:
Control:
Required Practical 4 – Enzymes
Investigate the effect of pH on the rate of reaction of amylase enzyme.
What does amylase break down?
How is the temperature controlled?
Hypothesis
Why do we use iodine?
Explain these results
Method
pH 3
pH 7
pH 9
pH 12
Enzyme Key words:
How could you improve the
Precision:
Accuracy:

5. What does a positive result look like? Emulsion test:
Required Practical 5 – Food tests
Use qualitative reagents to test for a range of carbohydrates, lipids and proteins.
Risk Assessment
Food tests
Test for Fat:
Test for Sugars:
Test for Protein:
Test for Starch:
Hazard
Risk
Control
Test tubes
Biuret reagent
Ethanol
Iodine
Water bath
What does a positive result look like?
Emulsion test:
Benedict’s reagent:
Biuret reagent:
Iodine test:
Suggested foods to be tested
Fat:
Carbohydrates:
Protein:
A student uses Benedict’s solution to test different foods for sugar. Suggest an explanation for these results.
Complete the table
Food tested
Final colour of Benedict’s solution A
blue B
brick-red C
green D
yellow
Reagent
Food group tested for
Colour before adding to food
Colour change if food group is present
colourless
starch
Benedict’s solution
Purple
The student says she was investigating continuous variables. Is she correct? Give your reasons. .

6. What is the inverse square law? - Higher
Required Practical 6 – Photosynthesis
Investigate the effect of a factor on the rate of photosynthesis using an aquatic organism such as pondweed.
Variables
Independent:
Dependent:
Control:
What is the inverse square law? - Higher
Label the diagram
Expected Graph
Hypothesis
Method
Calculate the mean and highlight any anomalies
Distance between the lamp and the pondweed in cm
Number of bubbles collected in minutes 1 2 3
Mean 5 
 35 33
37 
 10
30 
31  15 28 27 29 20 22 23 25 18 17 30 16 11 35 7 8
What can you say about the effect of the independent variable on the dependent variable? .

7. Number on the ruler in cm
Required Practical 7 – Reaction time
Plan and carry out an investigation into the effect of a factor on human reaction time.
Variables
Independent:
Dependent:
Control:
Risk Assessment and ethical considerations
Other possible ways to investigate reaction times
Hypothesis
Method
Calculate the mean and highlight any anomalies
Independent variable
Number on the ruler in cm
1st attempt
2nd attempt
3rd attempt
4th attempt
5th attempt
Mean
Silence 
 Music
Talking
After caffeine
How could you improve the
Precision:
Accuracy:
What can you say about the effect of the independent variable on the dependent variable? .

8. Results – Calculate the mean
Required Practical 8 (GCSE Biology only)
Investigate the effect of light or gravity on the growth of newly germinated seedlings.
Variables
Independent:
Dependent:
Control:
Describe two ways you could extend your experiment to do further investigations.
Label the diagram
Figure 1 shows some cress seeds that were grown in a box with light entering on one side. Explain the scientific reason for figure 1.
Hypothesis
Figure 1
Results – Calculate the mean
Explain why you used more than one seedling in each case.
Environment
Height of seedling in full sunlight in mm 1 2 3
Mean
Light 25
28 
27 
No light
 11
12  9 
How could you improve the
Precision:
Accuracy:
What can you say about the effect of the independent variable on the dependent variable? .

9. 5,3 22 2,6 43 7,2 29 1,8 Abiotic factor investigation
State the function of a quadrat
Required Practical 9 – Field Investigations
Measure the population size of a common species in a habitat. Use sampling techniques to investigate the effect of a factor on the distribution of this species.
Risk Assessment
Method
Results
Sample site Co-ordinates
Frequency of organism
Mean no of species present
5,3 22
2,6 43
7,2 29
1,8
Abiotic factor investigation
Distance along transect line (m)
Light intensity (lux)
% of grass cover 5
1,304 35 10
1,537 40 15
1,389 20
2,224 60 25
2,114 65 30
2,423
2,455
Your quadrat has an area of 0.25 m2 Calculate the mean number of species present per m2
Explain the effect of the abiotic factor on the % of grass cover.
Calculate the estimated population size .
Suggest any improvements you could make to the investigation to reduce any uncertainty in your results.

10. Explain why the decay of milk lowers the pH
Variables
Independent:
Dependent:
Control:
Required Practical 10 – Decay (GCSE Biology only)
Investigate the effect of temperature on the rate of decay of fresh milk by measuring pH change.
Explain why the decay of milk lowers the pH
Why is lipase used in this experiment?
How is the temperature controlled?
Expected Graph
Hypothesis
Results
Temperature of milk in °C
Time taken for solution to turn yellow, in seconds 1 2 3
Mean 20 30 35 32 40 10 11 9 60 5 7 8 80 6
Method
Two ways you could improve your experiment.
What can you say about the effect of the independent variable on the dependent variable?
How could you improve the
Precision:
Accuracy: .