9.11B Describe the biological factors affecting levels of food security,…

The idea

Food security means having reliable access to enough safe, nutritious food. Several biological factors reduce it. A growing human population raises demand for food, so supply per person can fall. Increasing animal farming and greater meat and fish consumption are inefficient because livestock and farmed fish need feed and land, so more resources produce less human food energy. New pests and pathogens can destroy crops or livestock, lowering yields. Environmental change caused by human activity, such as altered rainfall, higher temperatures or degraded soil, stresses crops and reduces harvests. Sustainability issues also matter: using land to grow biofuel crops competes with food production, and rising costs of agricultural inputs such as fertiliser, seed and fuel make farming less affordable.

What earns the marks

• An increasing human population raises demand for food, which can lower food security if supply does not keep pace.
• Increasing animal farming and higher meat and fish consumption are less efficient, because livestock and farmed fish consume feed and land that could otherwise produce plant food.
• New pests and pathogens reduce crop and livestock yields, threatening food supply.
• Environmental change caused by human activity, such as altered rainfall, higher temperatures or degraded soil, stresses crops and lowers harvests.
• Sustainability issues such as using land for biofuel production and the cost of agricultural inputs compete with or raise the cost of food production.

Common mistakes and how to put them right

• Confusing food security with food safety alone.

  Put it right: It is reliable access to enough safe, nutritious food, so supply and affordability both matter.

• Assuming more animal farming always means more food.

  Put it right: Livestock and farmed fish need feed and land, so it can be less efficient.

• Treating biofuel land use as harmless.

  Put it right: Land used for biofuels competes with land for food crops.

Exam tips

• Match each option to one named factor (population, animal farming, pests and pathogens, environmental change, sustainability).
• Reject options that are not biological or that would increase food supply rather than threaten it.
• For sustainability options, check whether they describe competition for land or rising input costs.