Cane toads were brought to Australia to eat beetles that damaged sugar cane crops. The toads ate few of the beetles. Instead, they ate many native animals and their numbers increased rapidly. What does this show about biological control?
The control organism may become a pest itself in its new habitat.
The control organism builds up in food chains like a pesticide.
The control organism only works when the crop is in a greenhouse.
The control organism causes the pest to become resistant to it.
127 exam-style questions on OCR GCSE Biology 6.2 Feeding the human race, covering 6.2.1 Biological factors affecting food security, 6.2.2 Agricultural solutions to growing demand, 6.2.3 Selective breeding, 6.2.4 Genetic engineering, 6.2.5 Steps in genetic engineering, 6.2.6 Benefits and risks of gene technology in agriculture, and 6.2.7 Biotechnological solutions to growing demand. Each one has a worked solution and a mark scheme showing where the marks go.