Students should be able to describe and explain some possible biotechnical…

The idea

A growing human population needs more food, and biotechnology and agriculture can help meet that demand. Genetic modification (GM) involves transferring a gene for a desired characteristic from one organism to another. For example, GM crops can be made resistant to insect pests or to herbicides, or to contain extra vitamins. This can increase crop yields and reduce losses. Other solutions include using fertilisers to supply minerals for growth, using pesticides to reduce pest damage, and improving irrigation to provide water. Selective breeding of livestock and crops can also raise productivity. These approaches must be balanced against concerns such as cost, environmental impact and food safety.

What earns the marks

• State that a growing human population increases demand for food.
• Describe genetic modification as the transfer of a gene for a desired characteristic from one organism to another.
• Explain how GM crops can increase yield, for example by giving resistance to pests, disease or herbicides.
• Describe other agricultural solutions such as fertilisers, pesticides, irrigation or selective breeding.
• Explain how each solution helps meet the demand for food, for example by reducing crop losses or increasing growth.
• Recognise that solutions have limitations or concerns, such as cost, environmental effects or ethical issues.

Common mistakes and how to put them right

• Thinking that genetic modification is the same as selective breeding.

  Put it right: GM transfers genes between organisms, often different species, while selective breeding chooses existing individuals to breed.

• Assuming GM crops always increase yield without any drawbacks.

  Put it right: Benefits depend on conditions and there may be environmental or economic concerns.

• Confusing fertilisers with pesticides.

  Put it right: Fertilisers supply minerals for growth, while pesticides kill pests that damage crops.

Exam tips

• Name a specific example of a GM crop and state the characteristic it has been given.
• For each solution, explain the link between the method and increased food supply.
• If asked to evaluate, give both a benefit and a concern for the solution you describe.