A laboratory grows one species of bacterium isolated from garden soil in nutrient broth. The broth initially contains 75 bacterial cells.
A student predicts that after 8 rounds of division the culture will contain 75×38 75 \times 3^8\,75×38 bacteria. The student thinks that each parent bacterium remains in the culture alongside the two cells it produces.
Explain the error in the student's prediction.
Calculate the number of bacterial cells in the culture when 8 complete rounds of division have occurred. Give your answer in standard form.
The laboratory records a mean division time of 35 minutes for this culture.
Calculate how long the culture takes to complete 8 rounds of division. Give your answer in hours and minutes.
282 exam-style questions on AQA GCSE Biology 1.1 Cell structure, covering 1.1.1 Eukaryotes and prokaryotes, 1.1.2 Animal and plant cells, 1.1.3 Cell specialisation, 1.1.4 Cell differentiation, 1.1.5 Microscopy, and 1.1.6 Culturing microorganisms. Each one has a worked solution and a mark scheme showing where the marks go.