A virus particle has a diameter of 1 × 10-7 m. A human cheek cell has a diameter of 6 × 10-5 m.
Calculate how many times larger the diameter of the cheek cell is than the diameter of the virus particle.
One infected cell releases 1.5 × 104 new virus particles. A sample contains 2 × 103 infected cells.
Calculate the total number of virus particles released by the infected cells in the sample. Give your answer in standard form.
Calculate the total length of these virus particles if they were placed end to end. Give your answer in mm\text{mm}mm.
A student checked the answer to (b) by rounding the numbers to 104×10310^{4} \times 10^{3}104×103.
Explain why this estimate is useful.
48 exam-style questions on Edexcel GCSE Biology 1.2 Number, size and scale, covering 1.2.1 Number, size and scale with estimations and 1.2.2 Quantitative units in relation to cells. Each one has a worked solution and a mark scheme showing where the marks go.