a) explain the importance of sugars, fatty acids and glycerol, and amino acids in the synthesis and breakdown of carbohydrates, lipids and proteins

b) describe the use of qualitative tests for biological molecules
PAG2

describe photosynthetic organisms as the main producers of food and therefore biomass for life on Earth

describe some of the substances transported into organisms in terms of the requirements of those organisms, including dissolved food molecules

describe different levels of organisation in an ecosystem from individual organisms to the whole ecosystem

explain the importance of interdependence and competition in a community

describe the differences between the trophic levels of organisms within an ecosystem

describe pyramids of biomass and explain, with examples, how biomass is lost between the different trophic levels

calculate the efficiency of biomass transfers between trophic levels and explain how this affects the number of organisms at each trophic level

recall that many different substances cycle through the abiotic and biotic components of an ecosystem, including carbon and water

explain the importance of the carbon cycle and the water cycle to living organisms

explain the role of microorganisms in the cycling of substances through an ecosystem

calculate the percentage of mass, in the context of the use and cycling of substances in ecosystems

explain the effect of factors such as temperature and water content on rate of decomposition in aerobic and anaerobic environments

calculate rate changes in the decay of biological material