Science at key stage 3    (Year 9)

• construct a food web showing feeding relationships of humans
• explain the meaning of terms, eg producer, consumer, energy source, herbivore, in relation to food chains

• identify which part of a plant is food for humans
• identify, from experimental results, starch stores in some plants
• name some materials produced as a result of photosynthesis
• describe how plants respire
• relate knowledge of the products of photosynthesis to ideas about plants as sources of food for humans and other animals

• make and explain connections between the use of plants for food and photosynthesis and its products

• find information about fertilisers and plant nutrients and summarise it in a table
• identify a range of minerals that plants need for healthy growth
• describe how fertilisers supply these minerals to crop plants

• identify relevant factors, eg concentration of nitrate, mass of fertiliser
• choose an adequate sample size to deal with variation between individual plants
• choose an appropriate timescale for measurements
• identify differences in growth and relate these to variables, eg composition, mass, of fertiliser used
• give reasons why they have or do not have confidence in their conclusions

• describe ways in which weeds compete with crop plants for resources from the environment
• describe how treating fields with selective weedkillers affects specific food webs
• explain how animals are affected by the removal of a particular food plant
• suggest how a high crop yield might be attained alongside preservation of animals' food supply

• follow their plan to collect data about the population and distribution of weeds
• produce appropriate tables and graphs to present data
• write a report for a third party in a suitable format, using scientific terminology effectively and accurately

• identify some common animals, including pests, which feed on crops and explain that they compete with humans for these resources
• explain how the elimination of pests will affect the populations of predator animals such as birds, relating explanations to pyramids of numbers

• describe how a persistent toxic material passes up a food chain
• explain why pesticides and weedkillers are used, identifying the dangers
• evaluate the information provided, relating it to the standpoint of the author of the text

• describe the views of different people who write about pesticides
• identify advantages and disadvantages of pesticides, and people to whom each will be important

• identify environmental factors which have influenced the growth of plants
• suggest some advantages and disadvantages of growing crops in a greenhouse

• present an annotated drawing of a design for a commercial greenhouse, relating this to knowledge and understanding of plant growth
• describe the benefits and drawbacks of greenhouse crop development

• summarise understanding of an issue, incorporating appropriate scientific knowledge and understanding, and explain with examples, eg
• how a stable ecosystem is one in which there is a balance of organisms
• how human development can have a harmful effect on the living things in an area
• how sustainable development involves an approach which aims to have minimal impact on the environment and living things