The organism Agrobacterium tumefaciens can be used to genetically modify tomato plants - Edexcel - GCSE Biology - Question 4 - 2017 - Paper 1

The process involves the following steps:

1. Insertion of Gene: First, the gene responsible for producing flavonoids is inserted into a plasmid.
2. Transformation: The Agrobacterium tumefaciens is then used to transform tomato plant cells by introducing this plasmid.
3. Selection of Transformed Cells: Cells that successfully integrate the plasmid are selected for further development.
4. Plant Regeneration: These cells are cultured and grown into full plants, resulting in 'purple tomatoes' that have enhanced flavonoid levels.

One advantage of genetic modification in 'purple tomatoes' is that it improves the nutritional quality of the tomatoes by increasing the levels of flavonoids. These compounds are known for their antioxidant properties, which may contribute to better health outcomes for consumers.

Growing herbicide-resistant corn allows farmers to use herbicides without damaging the crop. This means they can effectively eliminate weeds, which compete for resources such as water and nutrients. As a result, the corn can grow more robustly, leading to higher yields and contributing to an increased food supply.

The ladybird can increase crop yield by acting as a natural predator of the European corn borer. By feeding on these pests, ladybirds reduce their population and minimize the damage caused to corn plants. This biological control method helps in maintaining healthy crop conditions, resulting in improved yields.