Paper 1- 2022

• A student determined the size of a cell structure from a photograph obtained using a microscope.

  He used a ruler and a calculator and gave the answer in μm.

  Describe how the student determined the size of the structure.

  Measure and divide by magnification.

  Convert to μm from cm.
• Name two features of HIV particles that are not found in bacteria.

  Capsid

  Reverse transcriptase.

  RNA genome.

  Envelope.
• What is a tumour?

  Abnormal cells caused by uncontrolled mitosis.