A technician tells students to hold the lid of the Petri dish on with four short pieces of tape, rather than sealing it all the way round. Why?
Sealing it completely would let microorganisms in the air enter the dish
Sealing it completely would let microorganisms that respire without oxygen grow
Sealing it completely would stop the agar jelly from setting firmly in the dish
Sealing it completely would stop condensation from collecting inside the lid
163 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.