Practical questions

You will complete ten required practical activities if you are studying GCSE Biology and 21 if you are studying GCSE Combined Science. You could be asked questions about the methods, safety precautions you might take, results and conclusions of these experiments.

In this section there are three required practical activities:

  1. Required Practical Activity 1: Examination of plant and animal cells using a light microscope and production of labelled scientific drawings from observation
  2. Required Practical Activity 2: Investigation into factors affecting enzyme action
  3. Required Practical Activity 3: Qualitative identification of starch (iodine), glucose (Benedict's) and protein (biuret)

Sample question 1 - Foundation

Question

A student is investigating the process of mitosis with a microscope.

The hazard warning label on the chromosome stain they use states:

  • may cause skin irritation
  • may cause eye irritation
  • may be harmful if swallowed
  • non-flammable

Suggest three safety precautions they should take. [3 marks]

This question has been written by a Bitesize consultant as a suggestion to the type of questions that may appear in an exam paper.

They should avoid contact with hands/skin. They could also wear gloves. [1]

They should wear safety goggles. [1]

They should wash their hands after handling the bottle or slide. [1]

Sample question 2 - Foundation

Question

Describe how to prepare a stained slide of onion epidermal tissue. [6 marks]

This question has been written by a Bitesize consultant as a suggestion to the type of questions that may appear in an exam paper.

  1. take an onion bulb and remove one of the leaves
  2. peel a piece of inner epidermis from the leaf using forceps
  3. trim the piece of epidermis and place in one drop of water on a microscope slide
  4. lower a coverslip on top, taking care not to trap any air bubbles
  5. place one drop of iodine solution next to the coverslip
  6. draw the iodine solution under the slide by placing a piece of filter paper on the other side of the coverslip

[6]

These are the main points that the examiner will be looking for but you do not have to match every word.

In questions based on required practicals, the examiner will make allowances for instances where the equipment used in one school may be slightly different from another, the level of detail you've added, or if your answer is worded in a slightly different way.

Sample question 3 - Higher

Question

How would you show that living peas produce heat? Describe this in detail. The apparatus and materials for this investigation are listed below. Your account must refer to the order in which you set up the equipment. Include a suitable control. [6 marks]

  • two vacuum flasks
  • two thermometers
  • cotton wool
  • liquid disinfectant
  • living peas
  • dead peas

Diagrams in your answer will not give you any marks.

Question courtesy of Eduqas.

Things that should be included in the answer:

  • use of disinfectant to wash both sets of peas
  • fill an insulated flask with the living peas
  • the dead peas act as control
  • the same mass/volume/number of peas should be used in both flasks
  • place a thermometer into the peas
  • put cotton wool into the neck of the flask
  • record temperature at regular intervals/every hour/every day/stated times
  • compare temperatures in both flasks

[6]

As the question states that you must refer to the order in which you would set up the apparatus, it would be a good idea to write the answer as a numbered method rather than a flowing paragraph.

Sample question 4 - Higher

Question

Describe how you would set up a microscope to examine a prepared slide under high power. [6 marks]

This question has been written by a Bitesize consultant as a suggestion to the type of questions that may appear in an exam paper.

  1. select the lower power objective
  2. move the stage as close to the objective as possible
  3. place the prepared slide on the stage
  4. focus away from the slide, using the coarse focusing adjustment, until the specimen is in focus
  5. move the high power objective in line with the slide
  6. use the fine focusing adjustment to bring the specimen back into focus
  7. if the specimen cannot be brought back into focus, refocus under low power and repeat stages 5-6

[6]

It is important that this is written as a method and structured so that it can be followed in a logical order.