Specified practical 1.1

Examination of plant and animal cells using a light microscope and production of labelled scientific drawings from observation

Preparing biological samples for examination

Aims of the experiment:

  • to stain cells for examination with a light microscope
  • to examine a range of cells and other structures with a microscope to understand their basic structure
biological samples for examination

Making a slide of animal cells

Cheek cells

When viewing any slide with a microscope, a small square or circle of thin glass called a coverslip is placed over the specimen. This protects the specimen and prevents it from drying out when it's being examined.

When carrying out a practical activity a risk assessment should be completed first. For example:

HazardRiskControl measure
Name the chemical or apparatus in the experiment and give a reason why it is a hazard.Identify a step in the method where there is a risk of this hazard causing harm.Identify how you can minimise the risk.
Methylene blue is harmful and/or an irritant.Could irritate the skin if it gets on the hand while lowering the coverslip. It could be transferred from the fingers to the eyes.Wear gloves and eye protection. Use low concentrations of the chemical.
Question

Another hazard associated with the experiment is the thin glass coverslips. Complete the risk assessment for this hazard.

HazardRiskControl measure
Name the chemical or apparatus in the experiment and give a reason why it is a hazard.Identify a step in the method where there is a risk of this hazard causing harm.Identify how you can minimise the risk.
Glass is easily broken and is sharp.It can cut the skin when trying to lower it onto the slide.Handle carefully, report breakages.