Two species of duckweed, P and Q, both grow on the surface of ponds and both need light and mineral ions. Species P is introduced to a pond that contains only species Q. After two years, only species P is found in the pond. Which conclusion is best supported by this information?
Species P outcompeted species Q for light and mineral ions
Species Q was killed by a new pathogen carried by species P
Species P is a predator that fed on all of the species Q plants
Species Q has now become extinct in every pond in the country
63 exam-style questions on AQA GCSE Biology 7.1 Adaptations, interdependence and competition, covering 7.1.1 Communities, 7.1.2 Abiotic factors, 7.1.3 Biotic factors, and 7.1.4 Adaptations. Each one has a worked solution and a mark scheme showing where the marks go.