Practical questions

You could be asked questions about the methods, safety precautions you might take and results and conclusions of experiments that you have carried out during the course. You may also be expected to apply your knowledge to unfamiliar practicals, but draw on your practical skills.

Sample question 1 - Foundation

Question

A type of pesticide called fungicide can be used to kill fungus.

Scientists are investigating how well the fungicide works.

They also want to see if it works better if they add a chemical called a sticking agent.

This helps the fungicide stick to the banana leaves.

The scientists grow banana plants in four blocks.

The table shows the treatments each block is given.

Block	Fungicide	Sticking agent
A	✔	✔
B	✔	X
C	X	✔
D	X	X

A
Fungicide	✔
Sticking agent	✔

B
Fungicide	✔
Sticking agent	X

C
Fungicide	X
Sticking agent	✔

D
Fungicide	X
Sticking agent	X

Why did the scientists include the treatments given to block C and block D? [2 marks]

OCR Gateway, GCE Biology, Paper J247, 2016.

Sample question 2 - Foundation

Question

Scientists were studying how a fungal disease has spread through four different plant populations when they were treated with 4 different fungicides A,B C and D.

After a few months the scientists gave the plants in each area a disease rating.

The higher the rating the more disease present.

Block	Disease rating
A	20
B	35
C	45
D	60

Block	A
Disease rating	20

Block	B
Disease rating	35

Block	C
Disease rating	45

Block	D
Disease rating	60

What conclusions could the scientists make from this study? [2 marks]

Use data to support your answer.

This question is worth three marks so make sure you make three points AND include data.

OCR Gateway, GCE Biology, Paper J247, 2016.

Sample question 3 - Higher

Erythromycin is an antibiotic drug.

It is important to get the dose of erythromycin right.

Too much erythromycin can be harmful.

However, recently some strains of bacteria have developed resistance to low concentrations of erythomycin.

To see how effective erythomycin is, it is tested using bacteria grown on agar plates.

The method is used:

A petri dish is used that has the bacteria growing evenly over the surface.
A disc of filter paper is soaked in erythomycin
The disc is placed on the agar in the centre of the petri dish using sterile forceps
The dish is incubated at 37°C

Question

(i) Why did the scientists incubate the dish at 37°C rather than at higher or lower temperature? [2 marks]

OCR Gateway, GCE Biology, Paper J247 - Higher, 2016.

Question

(ii) Why is the filter paper disc moved using sterile forceps? [1 mark]

OCR Gateway, GCE Biology, Paper J247 - Higher, 2016.

Sample exam questions - global challenges - OCR Gateway Practical questions