← Combined Science syllabus

EnglandCombined Science

Biology: Community level systems

6 dot points across 6 inquiry questions. Click any dot point for a focused answer with worked past exam questions where available.

How do organisms interact in ecosystems, and how are carbon and nitrogen recycled?

Levels of organisation in an ecosystem, biotic and abiotic factors, interdependence and competition, the carbon cycle and the nitrogen cycle, decomposition, biodiversity, and human impacts on the environment.
A focused answer to the OCR Gateway GCSE Combined Science A topic B4 on community level systems, covering levels of organisation, biotic and abiotic factors, interdependence and competition, the carbon and nitrogen cycles, decomposition, biodiversity and human impacts.
9 min answer →

How is genetic information stored in DNA, and how are characteristics inherited from parents?

DNA, genes and chromosomes, sexual and asexual reproduction, meiosis producing genetically varied gametes, dominant and recessive alleles, genotype and phenotype, Punnett squares and inheritance ratios, and inherited disorders.
A focused answer to the OCR Gateway GCSE Combined Science A topic B5 on genes and inheritance, covering DNA, genes and chromosomes, sexual reproduction and meiosis, dominant and recessive alleles, genotype and phenotype, Punnett squares and ratios, and inherited disorders.
9 min answer →

What causes disease, how does the body defend itself, and how are new medicines developed?

Communicable and non-communicable diseases, types of pathogen and how they spread, the body's defences and the immune system, vaccination, antibiotics and the development and testing of new drugs.
A focused answer to the OCR Gateway GCSE Combined Science A topic B6 on health and disease, covering communicable and non-communicable disease, pathogens and their spread, the body's defences and immune system, vaccination, antibiotics, and the testing of new drugs.
9 min answer →

How do hormones coordinate the body more slowly than nerves, and how is blood glucose controlled?

The endocrine system and the role of hormones, the control of blood glucose by insulin and glucagon, type 1 and type 2 diabetes, the reproductive hormones and the menstrual cycle, and a comparison of nervous and hormonal control.
A focused answer to the OCR Gateway GCSE Combined Science A topic B3 on hormonal coordination, covering the endocrine system, control of blood glucose by insulin and glucagon, type 1 and type 2 diabetes, reproductive hormones and the menstrual cycle, and how nervous and hormonal control compare.
9 min answer →

How does the nervous system detect and respond to changes, and how is the internal environment kept steady?

The structure of the nervous system, the reflex arc and the role of synapses, receptors and effectors, the principle of homeostasis, and the control of body temperature, blood glucose and water as examples of negative feedback.
A focused answer to the OCR Gateway GCSE Combined Science A topic B3 on the nervous system and homeostasis, covering the central and peripheral nervous systems, the reflex arc and synapses, receptors and effectors, and homeostasis as negative feedback controlling temperature, glucose and water.
9 min answer →

Where does variation come from, and how does natural selection drive evolution?

Genetic and environmental causes of variation, mutation, evolution by natural selection, evidence from fossils and antibiotic resistance, selective breeding, genetic engineering, and the work of Darwin.
A focused answer to the OCR Gateway GCSE Combined Science A topic B5 on variation and evolution, covering genetic and environmental variation, mutation, natural selection and Darwin, evidence from fossils and antibiotic resistance, selective breeding and genetic engineering.
9 min answer →